project v4 – flank - L`Istituto

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Project V4 – Flank
PROJECT V4 – FLANK
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Project V4 - FLANK
Hazards related to the flank dynamics at Mt. Etna
Coordinators:
Giuseppe Puglisi, Istituto Nazionale di Geofisica e Vulcanologia, Sezione di Catania,
Piazza Roma, 2, 95123 Catania, Italy, [email protected]
Valerio Acocella, Dipartimento Scienze Geologiche Università Roma Tre, Largo S.L.
Murialdo, 1, 00146 Roma, Italy, [email protected]
Objectives
Many active volcano flanks show clear evidence of an activity resulting from several
causes including magma ascent along the feeding system and conduits, gravity force, local
and/or regional tectonic activity. Such factors may interact in a complex way with each
other and with the intrinsically complex volcano system. The result is quite often an
increased difficulty of a straightforward interpretation of the observed phenomena (e.g.,
ground movement, seismicity) for an effective evaluation of the volcano hazards, as it was
the case with Mount St. Helens volcano in 1980.
Among the Italian volcanoes, Mount Etna shows the most relevant case of active flank
dynamics along its East and South-East sectors, with some well-known seismogenic
structures, such as the Pernicana fault, or highly evident morphologies, such as the Valle
del Bove. Recent volcanic crises such as that of 2002-03 have been associated with seismic
activity in the East sector of Mount Etna (e.g., Santa Venerina – Santa Tecla fault) causing
relevant concern and implying further troubles in the scientific and Civil Protection
management of the crises.
Despite the above evidences, the large scale eastern flank instability of Etna is still today
the subject of debate, and in-depth dedicated research is necessary, with the aim of
evaluating the influence of the geodynamic setting (geology, tectonics, etc.), its
relationships with the volcano’s activity and the related hazard.
The aim of the present project is that of understanding the relationships between the preeruptive and eruptive dynamics, the shallow feeding system, and the tectonics on the East
volcano sector. This will be achieved through i) a better definition of the structural and
lithostratigraphic setting of the shallow portion of the volcano in critical sectors like those
of the Timpe or the Rift; ii) an in-depth investigation of the dynamics of the main active
tectonic structures; iii) the analysis of the relationships between volcanic activity and flank
dynamics; iv) a detailed study of movements in the submerged sector of the volcano. A
proposal for modification/innovation of the present monitoring system at Mount Etna will
be a qualifying project outcome. This approach will allow improving the knowledge on the
factors controlling flank instability at various scales on the volcano. This wide-ranging
analysis of the flank dynamics at Mt. Etna will be also useful to define areas and processes
relative to specific, potentially hazardous instabilities, from possible sudden, massive flank
collapses of a portion of a volcano to localized creep-like movements.
The research in the project will include the following steps:
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a. integration of geo-volcanological, geophysical and geochemical data already
available in order to define the areal extent of the volcano side subject to
movements and plan geophysical investigation aimed at determining its thickness.
b. Geo-volcanolgical studies on selected reference cases aimed at the definition of the
relationships between the shallow feeding system and the flank dynamics.
c. Geophysical and geochemical investigation (including the submerged portion of the
volcano) aimed at a better characterization of the lithostratigraphic units and
tectonic structures at depth, also addressed at the individuation of potential
surface/s of instability.
d. Modelling of geophysical, geochemical and geo-volcanological data aimed at
establishing the relationships between magmatic and tectonic structures and their
effects on the parameters recorded by the monitoring network.
e. Formulating proposals for the improvement of the monitoring system.
f. Study of systems for the evaluation of the hazard from flank dynamics related to
the occurrence of volcanic and/or seismic events.
Espected products
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Data employed in the project, organized in a GIS database.
3D definition of sectors of the volcano affected by flank dynamics.
Characterization of geo-volcanological aspects of reference volcanic events and
medium-long term evaluation of the effects on the flank dynamics, including the
characterisation and analysis of time-space patterns of the geophysical and
geochemical signals recorded.
Numerical simulations aimed at defining relationships between pre-eruptive and
eruptive dynamics and surface stress field.
Detailed mapping of seismic hazard for the main active structures of the East sector
of the volcano, including the relationships with the volcanic dynamics.
Evaluation of the hazard deriving from flank dynamics at Mount Etna, and
guidelines for a possible improvement of the monitoring system.
Feasibility study for the realization of an interface at the Functional Center of DPC,
to be agree upon with the same DPC, for the seismic hazard mapping described
above.
State of the art of the ongoing researches related to the present objectives
The tectonic framework of Mt. Etna is dominated by a N-S trending direction of
maximum compression, due to the Eurasia-Africa plates collision, and a related E-W
trending direction of maximum extension, associated with the development of the Malta
Escarpment, the possible surface expression of a tear in the subducting Ionian slab (see
Bousquet and Lanzafame, 2004, for a review).
Significant portions of the eastern and south-eastern flanks of the volcanic edifice are
characterized by down-slope movements, occurring with extremely different rates, from
mm/yr to cm/yr, up to m/week during some eruptive events. On the northern part of the
eastern flank, there is a general agreement that the boundary of the unstable sector is
represented by the E-W trending Pernicana Fault System, extending from the NE Rift to
the coastline, with a predominant left-lateral motion. Here the flank shows a predominant
ESE slip (Neri et al., 2004, and references therein).
To the south, the slip of the flank appears less consistent, being directed towards SE
and S, and controlled by several structures, with different geometry and kinematics.
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Among these, are the NNW-SSE striking Timpe Fault System (TFS), considered as the
onshore continuation of the Malta escarpment. This fault system is made up of several
NNW-SSE-striking faults with transtensive dextral displacement and characterized by
shallow seismicity (1-2 km of depth).
The outermost structure confining the slip of the flank to the south is the N-S trending
dextral Ragalna Fault (Neri and Rust, 1996). In addition, the slip of the SE flank of Etna is
also characterized by the development of an E-W trending anticline, recognizable through
InSAR data (Froger et al., 2001). These suggest that the fold, dissected by NW-SE trending
dextral faults, probably continues off-shore. The spatial-temporal relationships between
these different structures (faults, with various geometry and kinematics, and folds) are still
poorly constrained.
While the structure of the on-shore and shallower portion of the unstable flank is
sufficiently known (even though more studies are needed to constrain the SE part), the
deeper part of the unstable flank is still largely unknown. For example, different depths for
its basal decollement(s) have been proposed. In fact, the base of the sliding sector has been
inferred to lie at 1-2 km above sea level (asl) (Bousquet and Lanzafame, 2001), at 1-3 km
below sea level (bsl) (Bonforte and Puglisi, 2003, Lundgren et al., 2005), at 5~6 km bsl
(Borgia et al., 1992; Neri et al., 2004) and at both shallow and deep levels (Tibaldi and
Groppelli, 2002). In addition, several authors have argued that the slip of the flank may
result from shallower and deeper magma intrusion [e.g., Borgia et al., 1992; Lo Giudice
and Rasà, 1992; Rust and Neri, 1996; Bonforte and Puglisi, 2003; Rust et al., 2005; Walter,
2005), suggesting a feed-back between gravity and magma emplacement within the
volcano (McGuire et al., 1990).
The unstable E flank of Etna is also characterized by a higher seismicity with regard to
the rest of the volcano (Gresta et al., 1990). This recently culminated, during the 20022003 eruption, in the destructive events of S. Venerina, characterized by shallow epicenters
aligned along a NNW-SSE direction (Acocella et al., 2003). More in general, the 20022003 eruption, characterized by pre-eruptive and syn-eruptive seismicity, also
accompanying the slip of significant portions of the unstable flank, suggested the existence
of complex relationships between volcanic, seismic and flank activity.
The previously described state of the art deserves future investigations, summarized by
the following key questions:
- What is the spatial-temporal relationship between the different types of structures
accommodating the slip of Mt. Etna flanks?
- How deep is the flank slip?
- What is the relationship between flank slip and volcanic activity?
- What is the relationship between flank slip and seismic activity?
- Which are the main factors controlling the flank instability?
Description of the activities
Project FLANK aims at minimizing the hazards related to the instability of Etna flanks.
As shown in the previous section, this project will be focused on the E and S flanks, for
which geological evidence of instability is widely proven. The hazards resulting from flank
instability concern, in general, seismic and volcanic activity; therefore, most of the project
is focusing at facing the hazard possibly deriving from these processes. However, in some
cases, restricted to specific areas of the volcano, flank instability may lead to surface
fracturing and/or creeping processes, as well as to the development of landslides. A part of
this project will focus on the hazard deriving from surface fracturing, creep-like processes
and landslides at selected areas.
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In general, this Project will significantly rely on previously collected data, either those
produced and available in a previous DPC-INGV project (e.g. the Etna V3_6 project,
performed in 2005-2007) and those available from the monitoring systems implemented on
Mt. Etna from INGV, in the last decade. In fact, this combined dataset constitutes a
massive amount of geological, geophysical and geochemical information, which largely
waits to be analyzed and interpreted yet.
The availability of such a large amount of data will permit to: 1) have a
comprehensive and multidisciplinary view on the various processes characterizing flank
instability; 2) analyze, integrate and merge the existing data, also focusing, for the first
time, at defining the relationships between different datasets and processes; 3) highlight
specific activities (surveys and /or modeling), which still have to be carried out in order to
complete the data set or provide some unavailable parameters. In general, these activities
will provide collecting all the required new data within the first part of the project, in order
to interpret and make the data available to the project within the second part.
In order to ensure coordination and cooperation with the Project V3 – Lava, we
intend, in agreement with the Lava Coordinators, to organize jointly the kick-off meeting
of the two projects. Additional informal meetings between Task leaders of the two Projects
will also take place with the same aim.
To achieve its goal, the Project is structured in Tasks, each considering a specific
expected product, listed in the “Objectives” section.
In particular, Task 1 will be devoted to the implementation of the database into a GIS
system.
Task 2 will be devoted to the definition of the 3D geometry and structure of the portion
of the volcano characterized by instability.
Task 3 will be devoted to define the geo-volcanological processes and their
relationships, also in the frame of the available geophysical and geochemical data, both on
the long and the short term.
Task 4 will be devoted to model (with constraints from Tasks 2 and 3) specific aspects
of the instability of the flank, including stress, strain, triggering factors, cause/effect
relationships, stability conditions.
Task 5 will be devoted to produce (with constraints from Tasks 2, 3 and 4) detailed
maps of seismic hazard, associated to the main structures of the unstable flank, and to
evaluate the other hazards (volcanic, surface fracturing and creep) deriving from the
instability of the flank. These results will be merged in a synthetic form in prototypal
procedures for the evaluation of the hazard changes due to flank dynamics.
The figure below offers a synthetic synoptic view of all the activities. The successive
flow chart includes the roles of RU’s in the different Project activities, and illustrates the
finalization of the Project to a procedure for an integrated and multidisciplinary alert
system related to flank dynamics at Mount Etna. The activities of Tasks 2, 3, 4 and 5 are
grouped in WorkPakages in order both to facilitate the exchanges among different RUs
involved in similar activities and improve the quality of the final products. A detailed
description of the Tasks is provided below.
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Synthetic synoptic view of project activities
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Flow chart of Project achievements and products
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Task 1. GIS (Responsible: D. Reitano )
RU Participating: all
The large amount of data which will be used in the FLANK Project, either already
available at its onset (e.g. provided from the monitoring systems or previous projects) or
resulting from the planned activities, are widely multidisciplinary. This task is aimed at
implementing a web-GIS infrastructure able to manage the different types of data; the webinterface will be user-friendly and able to guarantee different access levels, if necessary. It
is planned that the web-GIS will be also able to disseminate the main selected results of the
project, in the case that the consortium wishes to present the project results to the wider
scientific community. This activity will be carried out in cooperation with LAVA project,
as it shares a large amount of data with the FLANK project. In particular, this cooperation
mainly results from the activity of the RU11 (team 1). More in general, joint meetings
(including the kick-off meeting) are planned between the LAVA and FLANK projects, as
well as a continuous exchange of information and data.
All RUs (Research Units) will implement their data sets into the database, at the onset
of the project if these are already available, or during the project, if the data must be
collected. Details on each data set type are provided into the applications of the different
RUs (see below). ). The database will be implemented with the aim of ensure the
maximum compatibility with the WOVOdat standards.
Task 2. Geometry, kinematics and structure of the “unstable” flanks
RU Participating: Valerio Cancella (RU-01), Andrea Argnani (RU-03), Francesco Chiocci
(RU-05), Ornella Cocina (RU-06), Cinzia Federico (RU-07), Francesco Mazzarini (RU09), Giuseppe Puglisi (RU-11), Agata Siniscalchi (RU-12).
The aim of this Task is to investigate the 3D structure (geometry and kinematics) of the
unstable flanks of Etna, with particular attention to the definition of the associated
deformations. This information will permit to: have a reference data set to evaluate any
relationship between the structure of the flank and volcanic and seismic activity (Task 3);
significantly constrain the results from numerical and analogue models (Task 4); provide
the basic information for any hazard evaluation (Task 5).
The Task is divided into 2 Work-Packages (WP): WP-2A, considering the surface
features and WP-2B, considering the features at depth.
WP-2A) Surface (Responsible: S. Branca)
This WP aims at gathering all the available surface information regarding the slip of
Etna flanks, both on-shore (i) and off-shore (ii). These two parts are characterized by the
following features.
i) Integration of the data concerning the main structural and kinematic features of the
on-shore portion of the “unstable” flanks. Most of these data have been previously
collected, largely by RU-11, even though focalized and local studies may be eventually
carried in the first part of the research, to better define specific features. The data set to be
analyzed and merged includes: field survey data (RU-11), gas emission data (RU-11, RU07), GPS, leveling and DinSAR data (RU-11), and SBAS velocity maps. The last one have
been already produced and analyzed by the CNR-IREA institute of Napoli. While this
institute will not be officially involved in the first stage of the project (appearing in RU-01,
though), an ongoing collaboration with some of the researchers participating in this project
will assure, under the responsibility of the coordinators, the availability of the SBAS
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velocity maps. The aim of this part of the project is to provide a comprehensive
multidisciplinary frame, including the area(s) characterized by a consistent slip, as well as
the major and minor structures through which the motion occurs.
ii) Interpretation and integration of different data sets, to identify the main geological
and structural features of the proximal and distal of the unstable flank in the off-shore
domain. These data sets include a detailed bathymetry (RU-05; RU-03) and seafloor
sampling (RU-05), whose results will be related to the on-shore coastal portion, in
collaboration with RU-11. Except for seafloor sampling, all of the remaining data sets have
been already collected by the RUs. Seafloor sampling will be performed in the first part of
the project, and will be focused at specific locations of particular interest. Attention will be
devoted, in this part, to the definition of the main geological (nature and age of deposits)
and structural (faults and folds) features characterizing the off-shore unstable portion, as
well as the definition of its aerial extent.
WP-2B) Depth (Responsible: O. Cocina)
This WP aims at collecting new data and gathering them with all the already available
information regarding the geometry of deep structures of Etna flanks. The activities will be
carried out in this WP are the following.
i) Interpretation and integration of all the available subsurface well-data on the onshore
portion of the unstable flanks (RU-07). These will permit to define the main lithotypes at
depth, including the configuration of the top of the sedimentary substratum, below the
volcanic pile. Moreover, the well-data (most of them built for water purposes), in addition
to the available spring data, will permit to define the depth, extent and volume of the main
aquifer(s) of the E and S flanks. This evaluation will be particularly useful to best interpret
the shallow geophysical results (resistivity and magnetotelluric), partly previously acquired
and, partly, to be acquired in this project, from RU-12. Additionally it will represent an
important data for the definition of the geological and hydrogeological model in
performing the stress-strain analysis include in task 4 from RU-02.
ii) Deeper geophysical analysis of the on-shore portion of the unstable flanks (RU-06).
This will consist of the following two studies. Application and implementation of seismic
tomography techniques for the definition of the 3D velocity tomography (VP and VP/VS
tomographies) and attenuation structure (Qp models) of the deeper portion of the unstable
area. High precision locations of seismic events also focused at recognizing the most
important seismogenetic structures. This study will permit to evaluate the deeper structure
of the on-shore unstable portion.
iii) Resistivity and magnetotelluric properties of selected portions of the unstable flank
(RU-12). This study will be characterized by the following two activities. Continuation of
the previous promising studies along the Pernicana Fault (NE sector), which permitted to
infer a possible depth for the basal decollement of the unstable sector; the aim of this
activity, in the present project, is to provide definitive constraints on the structure and
depth of the decollement in the northern part of the unstable flank. Definition of the
relationships among different structures characterizing the slip of the SE flank (faults with
different orientation), by constraining their deeper extent. All these data will be collected
in the first part of the project and will be of particular interest to define the local extent of
the on-shore structures, as well as the deeper extent of the unstable sector in the NE and SE
portions of the volcano. This information will be particularly useful for Task 4 and, in part,
for Tasks 3 and 5.
iv) Interpretation of the existing data sets of seismic lines, devoted at understanding the
deeper geology and structure of the off-shore portion of the eastern flank. In particular, two
recently acquired seismic data sets are available: a shallower, high resolution, one (RU-09)
and a deeper one (RU-03). While the first data set will permit to investigate the details of
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the shallow structure, as well as the structural and stratigraphic relationships of the offshore flank, the second data set will permit to define the deeper structural and stratigraphic
features, as well as the relationships with the regional tectonic structures, outcropping
immediately to the south of the investigated area, along the Malta escarpment. Both data
sets will be compared and integrated, in order to provide a general and consistent frame,
through the experience of the researchers and geologists involved to analyze the seismic
marine profiles and the morpho-bathymetric data, to define the structural features and the
debris avalanched deposits. In addition, these results will be also integrated with those
collected by RU-5, and subsequently with those available in the on-shore portion (RU-11).
Task 3. Relationships between flank dynamics, eruptive activity and
geophysics/geochemistry data
RU Participating: Raffaele Azzaro (RU-04), Cinzia Federico (RU-07), Carlo Giunchi
(RU-08), Giuseppe Nunnari (RU-10), Giuseppe Puglisi (RU-11).
The aim of this Task is to define the possible cause/effect relationships between flank
dynamics and magmatic activity, in broader terms. Therefore, this Task will consider the
existence of any significant pattern in the geophysical, geochemical and geological
(volcanological, petrological, structural) available dataset, in relation to the episodes of
instability of the flanks of the volcano also considering available meteorological data. In
general, this information will be particularly useful to better constrain and validate the
numerical and analogue models of Task 4 and to provide an appropriate database for
hazard evaluation in Task 5.
This Task is divided into 2 Work-Packages (WP): WP-3A is focused on the LongTerm behavior and WP-3B on the Short-Term behavior.
WP-3A) Long term (last 300-400 years from catalogue data) (Responsible: G. Nunnari)
i) Analysis of the historical seismicity, from catalogue data (RU-04). This will, first of all,
permit to uniform, classify and parameterize the available dataset. Such an analysis will
also permit to characterize the behavior of the main seismogenic faults, through the
reconstruction of the curves of the seismic strain release, b value and occurrence models.
These analyses are expected to indicate how the faulting processes relate to eruptive
dynamics (emplacement of dykes) or larger-scale processes (instability of the flank,
offshore tectonics). These data will be of crucial importance to evaluate the hazard
deriving from seismic activity (Task 5).
ii) Analysis of the historical volcanic events, as well as of the related products, to define
the main eruptions, and associated features, related to the dynamics of the flank (UR-11).
In particular, the relationships between summit and flank activity in the frame of the slip of
the flanks (as during the occurrence of seismic events) will be investigated. The data will
be analyzed, from a statistical point of view, in collaboration with RU-10.
iii) Advanced statistical integrated analysis of the volcanic dataset provided by RU-04 and
RU-11, to define the long-term reference volcanic events and any self-organization in
volcanic activity related to flank slip (RU-10). Such an analysis will be focused on selforganized criticality theory (SOC), permitting to highlight possible behaviors, otherwise
difficult to identify, given the complexity of the problem. These data will be of particular
interest to constrain the models (Task 4) and evaluate the hazard deriving from seismic
activity (Task 5).
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WP-3B) Short term (1993-2004, monitoring data) (Responsible: M. Neri)
i) Assessment of a complete volcanological, geochemical and geophysical data-base. In
particular, the volcanological data-set will investigate the relationship between magmatic
activity (petrology of the erupted products, evaluation of the plumbing system) and flank
dynamics (RU-11). The geochemical features will include studies of shallow magma
degassing in soil and aquifer, through appropriate modeling (porosity and permeability,
fluid circulation) (RU-07). The geophysical features will include the study of long-period
LP earthquakes, as well as the definition of the polarization of earthquakes along the major
faults on the unstable flanks, both able to cause significant damage (RU-08). These studies
will be of particular importance for the analyses at points ii) and iii), as well as for Task 5
(in collaboration with RU-04, and RU-11).
ii) Analysis of each data-set aimed at characterizing the relationships between each
type of data and flank dynamics, e.g.: volcanological data (eruptive fracture
distribution/evolution, time-evolution of chemical features of volcanic products and related
erupted volumes), structural data (fault location, slip and size), geophysical data
(time/spatial-evolution of geophysical data, including GPS, seismic, gravity and magnetic
stations, definition of source mechanism of typical seismic events), geochemical data
(time/spatial-evolution of geochemical data from soils, at specific locations, and plumes)
(RU-11). This analysis will be performed in collaboration with RU-10.
iii) Multidisciplinary review analysis of the different data-sets (volcanology, structure,
geophysics, geochemistry), in relation to flank instability. This integrated study will be
performed by RU-11, in collaboration with RU-10. It will lead to an advanced automatic
multivariate statistical analysis, named data mining, consisting of the extraction of implicit
and potentially useful information from large collections of data (RU-10, in collaboration
with RU-11). Data mining will be focused on a selected database (namely seismic and
High-Frequency GPS data) and, through the classification of events, aimed at identifying
time/spatial patterns eventually related to the dynamics of the flank. The results of this
study will be of particular importance for modeling validation, in Task 4, and hazard
evaluation, in Task 5.
Task 4. Modeling
RU Participating: Valerio Acocella (RU-01), Tiziana Apuani (RU-02), Carlo Giunchi
(RU-08), Francesco Mazzarini (RU-09), Giuseppe Nunnari (RU-10), Giuseppe Puglisi
(RU-11).
This Task is aimed at providing the required simulations for DPC to define the
relationships between pre-eruptive and eruptive dynamics and the surface stress and strain
distribution. This problem will be faced by using both numerical and analogue models.
Both require an improvement of the knowledge of the basic parameters used in the models.
Thus, the activities of this Task are grouped into 3 Work-Packages (WP): WP-4A
(Definition of the parameters), WP-4B (Numerical models) and WP-4C (Analogue
models). The results of this Task will be exploited into Task 5, to assess the seismic and
volcanic hazard related to the flank dynamics. Moreover, consistent modeling results may
also help in better constraining the interpretation of the models deriving from the
geological and geophysical activities proposed in Task 2.
WP-4A) Definition of the parameters (Responsible: M. Pompilio)
Since the fundamental question of this Task is to assess the stress-strain relationship
between the structure of the volcano and the dynamics of magmas within the volcanic
“reservoirs” (in broad sense) or pathways, the basic parameters which will be investigated
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in this WP are i) those characterizing the mechanic and rheologic properties of rocks
forming the volcano and its basement and ii) those characterizing the pre-eruptive
conditions of the magma.
i) RU-08 will carry out tests to define both the physical properties (e.g. density and
porosity) and the mechanical parameters (e.g. static elastic modules) of main lithotypes.
These tests will provide also other information useful not only for the modeling, but also to
improve the analysis and interpretation of studies on seismic anisotropies carried out in the
Task 3; this is the case of the measurement of the seismic anisotropy of P ands waves. RU11 will provide an estimation of viscosity of sedimentary basement below selected areas of
eastern flank (along the Pernicana Fault) by exploiting the GPS measurements collected
during the 2002-03 eruption. The RU-2 will calibrate geotechnical models by integrating
the results specific geotechnical and geomechanical laboratory tests with other tests,
including those performed by RU-08.
ii) The definition of the pre-eruptive conditions in terms of pressure, temperature and
chemio- physical properties of magma will be achieved by petrologic study of products of
relevant eruptions. In particular the evolution of processes of degassing, decompression
and magma chamber refilling will be obtained from detailed studies of zoning of minerals
of selected eruptions. Such estimates will be obtained using current thermodynamic
modeling and results of experiments on phase-equilibria carried out by participants to RU09, during the previous DPC-INGV Etna Project. All the data will serve as input for
numerical modeling (WP-4B). Further specific laboratory experiments will be carried out
in order to improve the resolution of some parameters and to validate the above models.
WP-4B) Numerical models (Responsible: C. Giunchi )
The relationships between pre-eruptive and eruptive dynamics and the surface stress
and strain distribution will be investigated through three different approaches: i) one is
aimed at modeling the geodetic data, to infer on the stress-strain relationship related to the
flank dynamics; ii) the second deals with the relationships between magma equilibrium and
flank dynamics; iii) the third investigates the critical conditions generating flanks
instability through geotechnical modeling.
i) Several recent studies, based on analytical modeling of ground deformations of Mt.
Etna, allowed the identification of the major structures controlling the dynamics of the
eastern and south-eastern flank. However, these analytical studies cannot give satisfactory
answers in evaluating the cause-effect relationships among the intense geodetic strain
pattern, the stress that magmatic “structures” produce or suffer, the stress field originating
flank instability and the lively seismicity characterizing the eastern and southern flanks.
Numerical models may give suitable answers to these questions, with potential applications
to civil defence purposes. In this project, both Finite and Boundary Element Models (FEM
and BEM) will be used to assess the distribution of the static stress, with particular care to
its distribution along the main structures of the volcanic flanks. The 3D structural
assessment resulting from Task 2 will allow improvement of the meshing of the numerical
models. In particular, RU-08 will create a full model of the volcano, including topography,
the principal volcanic and seismogenic structures and the appropriate rheological behaviors
(e.g. anelasticity in proximity of volcanic sources). A sensitivity analysis will be also
performed to evaluate the stability of the FEM approach as functions of assumed structural
geometries and rheology. RU-11 will use FEM to compute synthetic Green’s functions that
will be combined with an inverse method to estimate the distribution of the dislocations of
the main seismogenic structures; these results will allow computation of the Coulomb
stress changes. The use of the BEM, which will be carried out by RU-10, may improve the
efficiency of numerical approaches due to the reduced numbers of mathematical
relations/parameters involved in this type of numerical modeling approach; specific
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comparison among the results of the different RU involved in the numerical modeling of
ground deformation will be performed.
ii) Numerical models to simulate the relationship between magma and host-rock will be
implemented by RU-09. Their aims are: understanding the pre-eruptive dynamics of
magmas, considering also the role of the arrival of new gas-rich magma into the
“reservoir”; evaluating the effects of external perturbations of the stress in triggering
magma convection and pressurization; estimating the effects on measured geophysical
parameters induced by the simulated dynamics. This activity will be performed by using
finite element numerical codes partially implemented and improved in previous INGVDPC Projects.
iii) RU-02 will implement numerical geotechnical models to evaluate the critical
conditions able to generate flank instability. This approach will consist of a 3D modeling,
successfully applied at Stromboli. This activity is aimed at defining the limit conditions for
static and dynamic (magma-induced) equilibrium, as well as the possible failure surfaces,
considering the different of various instability factors. These models will be partly based
on the parameters defined in WP-4A.
Particular attention will be given to study the role of porewater pressures on the
instability of the flanks of the volcano, especially throughout the activities at the point i)
and iii). In fact, porewater pressures changes have been suggested as one of the possible
triggers for flank slip at many volcanoes (e.g. Kilauea, Capo Verde, Canaries; Cervelli et
al., 2002, Elsworth and Day, 1999).
WP-4C) Analogue models (Responsible: C. Giunchi )
Analogue models of flank instability will be performed to evaluate the possible role of
topography, regional tectonics, magma emplacement (both dikes, at surface, and diapir-like
bodies, at depth), presence of decollements or anisotropies (RU-1). These models will be
validated by parallel-run numerical models (RU-1), sharing the same boundary conditions,
for a better validation. Subsequently, the models will be compared to other numerical
modes (UR-2, 8, 9, 11) and to the natural case (as derived from the constraints of Task 1
and Task 2), proposing a general comprehensive scenario relating flank slip to possible
triggering factors.
Task 5. Hazard (Responsible: R. Azzaro)
RU Participating: Raffaele Azzaro (RU-04), Giuseppe Puglisi (RU-11), all UR
This Task will deliver the products aimed at assessing the hazard deriving from the
flank dynamics and indicating the improvement/modification of monitoring system and
surveillance activities to reduce such hazard. The activities of this Task are grouped into 3
Work-Packages (WP): WP-5A (Seismic Hazard) and WP-5B (Integrated hazard) and WP5C (Results for monitoring/surveillance activities).
WP-5A) Seismic Hazard
Seismic hazard is, by far, one of the most relevant natural hazards of the eastern and
southern flanks of Mt. Etna. Although the magnitudes of the earthquakes has not exceeded
5, destructive events are relatively frequent (on average, the X degree of EMS on the
eastern flank is reached every 20 years), due the shallow sources. RU-04 is responsible for
the activities aimed at assessing the seismic hazard. The characterization of the seismic
potential of the active faults on the eastern flank will contribute to define the more
hazardous zones. The seismic potential will be evaluated by using both deterministic and
probabilistic approaches, partially based on the results of Task 2 (for the dimension of the
272
faults) and Task 3 (for the estimation of the b-value of the Gutemberg-Richter
relationship). Another preparatory study for seismic hazard assessment concerns the
definition of the intensity decay, which will be achieved by probabilistic techniques based
on appropriate analysis of earthquake database (which, in this project, will be extended up
to XVII century). Two types of seismic hazard maps will be delivered: a set of seismic
hazard maps, in terms of macroseismic intensity, for exposure times ranging from 5 to 50
years, and a set of time-dependent seismic hazard maps, computed for a few selected
seismogenic faults of the eastern flank, by applying a method adopted in the previous
INGV-DPC seismologic projects.
WP-5B) Integrated hazard
In this WP an analysis of the hazard deriving from the dynamics of the flanks of Etna
will be performed. Beside seismic hazard (see WP-5A), the other main flank hazards are
related to the opening of the fracture/eruptive fissure systems, the aseismic creep and the
triggering of landslides. All these types of hazard will be investigated by RU-11, in general
using information deriving from Tasks 2, 3 and 4. Furthermore, in this WP a preliminary
evaluation will be performed, to assess a probabilistic hazard by using the “event tree”
approach, in cooperation with LAVA project.
The “unstable” portion of Mt. Etna is bounded to the west, by the NE and S rifts. Their
activity, controlling the shallow rise of magma in the volcano, shows significant
relationships with flank dynamics. The analyses of Task 3 and 4 will be integrated with a
statistical analysis of the actual fracture/eruptive fissure system, to define the most suitable
areas of the volcano where they may occur. This activity will benefit of the joint researches
carried out in the frame of the LAVA project, based on probabilistic approaches, aimed at
defining the probability of opening of new vents. However, in this project, only the
relationships between volcanic activity and flank dynamics will be considered.
Flank instability deriving from different processes (magma, seismicity, porewater
pressure) will be also considered at smaller scales, defining the possible areas and
mechanisms controlling the instability. These smaller-scale instabilities may range from
collapses of portions of steepest flank of the volcano (e.g. collapses occurring in the Valle
del Bove) to localized creep-like movements (as those observed along the Pernicana Fault).
In particular, aseismic creep is relatively frequent on the eastern and southern flanks of
Mt. Etna, along several faults systems related to flank instability. Creep processes may not
have a primary importance for hazard assessment in uninhabited areas; however, they
become significant when affecting crucial infrastructures or properties. Therefore, one of
the aims of this activity will be the quantification (e.g. rate of movement, extent of the
affected areas) of the creep processes near the principal life-lines (e.g. the Catania-Messina
highway or the railway).
On the eastern flank, a few well-known faults are related to flank activity. These,
combined with local topographic conditions, enhance or trigger gravitational instabilities.
This type of hazard will be systematically considered, evaluated and adequately mapped.
The results of all the above described activities, together with the results of the seismic
hazard assessment, will be integrated to assess a final volcano-hazard evaluation.
WP-5C) Results for monitoring/surveillance activities
This WP will produce two deliverables of the project. All RUs will be involved into
their preparation.
The first deliverable consists of a document indicating the guidelines for an eventual
improvement of the monitoring system. This will consider all the results obtained in the
project and the simulations in particular (Task 4), indicating the areas were the major
273
changes in the geophysical/geochemical signals are expected, and the integrated hazard
assessment provided in the above two WPs of Task 5.
The second deliverable consists of prototypal procedures to be used by the Operations
Centre of DPC in case of unrest along the unstable flanks, highlighting possible changes in
hazard as a function of the changes in the state of the flank dynamics. These include
volcanic hazard (opening of fissures and fractures), seismic hazard (occurrence of
earthquakes) and stability hazard (creep-like movements, sudden, mass movements,
localized landslides). In particular, if the project (Task 3) will identify specific
relationships between seismic and volcanic activity, the procedures should consider these
results, possibly by identifying “type-events”, trying to estimate of the type of hazard and
its occurrence probability, considering certain boundary conditions. The details of this
deliverable will be agreed with the DPC.
274
4. List of deliverables
First Year
Task 1 - GIS
1. Database structure assessment; Site realization; Database integration (UR-11).
WP-2A) Surface
1. Map of integrated (on-shore and offshore) structural features (1:50.000 scale)
and map of selected features (1:10.000) (UR-05 and UR-11);
2. Integration of all the shallow water available data (UR-05 and UR-11);
3. Report on the oceanographic cruise with the R/V Universitatis (UR-05);
4. Structural analysis derived from the integration of surface surveys, geodetic
data and soil gas surveys (UR-11);
5. Definition of the main tectonic features related to flank slip (UR-11).
WP-2B) Depth
6. Analysis of seismic data, mostly marine seismic profiles, in order to identify
and correlate the main seismostratigraphic units. Identification and correlation
of the main tectonic structures on seismic profiles (UR-03);
7. Mapping of the distribution of the large-scale mass-wasting deposits located
offshore the eastern flank of Mt. Etna (UR-03);
8. Build-up of a relative chronology of tectonic activity and stratigraphic events.
Attempt of correlation of the identified seismic units to the onshore
stratigraphic units of known age (UR-03);
9. Data analysis of seismic data sets; 1D Vp and Vp/Vs models (UR-06);
10. Physical model of the volcano, with the identification of zone of different
permeability (UR-07);
11. Elaboration of some off-shore seismic lines across the possible prolongation of
the Mascalucia-Trecastagni faults. Analysis and interpretation of elaborated
seismic lines (UR-09);
12. MT and SP data acquisition in the northeastern flank; ERT profiles (acquisition
and modeling) on the southern flank (UR-12);
13. Integrated interpretation of the previous resistivity model with velocity and
density models (UR-12).
WP-3A) Long-term
14. Extension of the macroseismic catalogue from ≈1650 to 1831 (UR-04);
15. Analyses on fault behavior: strain release and b value (UR-04);
16. New insights about self organized critical (SOC) behaviors of volcanic areas
(UR-10);
17. Preliminary definition of the main eruptive events and their volcanological
features related to the flank dynamic (UR-11).
275
WP-3B) Short-term
18. New algorithms to process continuous GPS and seismic signals (UR-10);
19. Petrologic data set of selected volcanics from Summit Craters (UR-11).
Task 4. Modeling
WP-4A) Definition of the parameters.
20. Rock mechanical characterization of selected sites for modeling activities.
Physical and mechanical characterization of the main Etna lithotypes, and
definition of lithotechnical units (UR-02 and UR-08);
21. Microstructural characterization of the natural lithologies investigated (UR-08);
22. Definition of secondary seismic anisotropy (Voids space+texture) (UR-08);
23. Petrologic study of products of selected recent eruptions (UR-09);
24. Estimate of relevant pre-eruptive conditions within magmatic reservoirs feeding
recent eruptions. Development of combined analytical methods to obtain
detailed zoning profile in minerals (UR-09);
25. Inversion of time-dependent relaxation models by using GPS data time series
(UR-11).
WP-4B) Numerical models
26. First stress-strain numerical models of the unstable Etna flanks (UR-02);
27. Preliminary 3D FE model of the unstable flanks of Mt. Etna. Study of the role
of different sources (summit eruptions, deep pressurized reservoirs, regional
tectonic stresses) on the structural discontinuities and flank instability (UR-08);
28. System definition for the simulations of magma and rock dynamics. First
simulations on magma/rock dynamics (UR-09);
29. New algorithms to compute the Coulomb stress changes in the eastern flank of
Mt Etna (UR-10);
30. Developing and testing the FEM geodetic inversion procedure and numerical
code for evaluating the viscoelastic deformation (UR-11).
WP-4C) Analogue models
31. Set up of the experimental apparatus for analogue modeling (RU-01);
32. Definition of the input parameters (derived from WP 2B and 4A) and
production of the experiments simulating flank slip. Run of the numerical
experiments (RU-01).
Task 5. Hazard
33. Seismic potential of faults: deterministic approaches (RU-04);
34. New probabilistic relationships of intensity attenuation (RU-04).
35. Preliminary results of the parameterization of creep and landslide areas for
volcano-structural hazard evaluations (RU-11);
276
Second Year
Task 1 - GIS
36. Data representations, web interfaces, GIS; Final documentations; manuals (UR11);
37. Collection of the data sets for populating the database (all RU).
WP-2A) Surface
38. Report on scuba and ROV survey on selected targets (UR-05);
39. Characterization of the nature of possible mud volcanoes in the offshore
Pernicana Fault (UR-05);
40. Mapping and characterization of the tectonic elements cropping out on the
coastal zone (on land and offshore) (UR-05);
41. Analysis of the samples collected in the first-year cruise, and of all the collected
geophysical data (UR-05);
42. Interpretation of the offshore structural elements and of tectonic/large-scale
instability features possibly driving the movement of the eastern flank of the
volcano (UR-05);
43. Correlation between on- and off-shore tectonic structures and their relationship
to the eastern flank dynamic (UR-11).
WP-2B) Depth
44. Mapping of fault surfaces at depth on seismic profiles, to outline fault
geometry. Interpretation of tectonic structures at a large scale (UR-03);
45. Depth conversion of selected seismic profiles, to obtain a realistic geometry of
fault planes and a more accurate volume estimate of the offshore mass-wasting
deposits (UR-03);
46. Tectonic model describing the deformation affecting the offshore flank within
the regional tectonics frame (UR-03);
47. 3D numerical models of P- and S- wave velocities and of Qp and Qs (UR-06);
48. Precise locations on selected earthquake clusters occurring nearby seismogenic
structures (UR-06);
49. Database of earthquake locations relative to the period 2003-2004, including the
2004 summit eruption (UR-06);
50. Vertical and spatial distribution of the main fluid pathways (UR-07);
51. Elaboration of some seismic lines across the possible off-shore continuation of
the Pernicana Fault. Analysis and interpretation of elaborated seismic lines.
Correlation of observed structures with other seismic surveys (UR-09);
52. MT data acquisition along the Mascalucia-Acireale profile (UR-12);
53. Map of distribution of the geoelectrical strikes at different estimated depth (UR12);
54. SP map and Resistivity model (2D o 3D) for the areal survey in NE Rift area
(UR-12);
55. Resistivity model across the MT profile Mascalucia-Acireale and its integrated
interpretation of the profile (UR-12).
277
WP-3A) Long-term
56. 1. Analyses on fault behavior: occurrence models, Montecarlo simulations of
earthquake catalogues (UR-04);
57. Algorithm for measuring time series similarities, classification and clustering
(UR-10);
58. Recognition of the eruptive processes of the past 3-4 centuries related to the
activation of the main seismogenic faults (UR-11).
WP-3B) Short-term
59. Simulation of the effect of of the variation of the mass rate and/or pressure on
shallow geochemical manifestations during the past volcanic activity (UR-07);
60. Simulation of the effects of fluid mass rate and/or pressure on rock
characteristics (UR-07);
61. Map of directions of polarization. Attenuation of volcanic LP earthquakes (UR08);
62. Pattern recognition techniques to analyze multivariate time-series (UR-10);
63. Time-related petrologic sequence correlated with other temporally constrained
data-set concerning geology, geophysics and geochemistry of gases (UR-11);
64. Results of the review and the re-interpretation of eruptive and deformative
events during the period 1993-2004 (detailed results of specific volcanic events)
(UR-11).
Task 4. Modeling
WP-4A) Definition of the parameters.
65. Dynamic elastic moduli for lava flows at increasing effective pressure.
Microstructural characterization of the experimental products. Definition of
Primary seismic anisotropy (Texture) (UR-08);
66. Evaluation of elastic and geometrical parameters of the Pernicana area and
comparison with available geological and geophysical information (UR-11);
67. Petrologic study of products of relevant historical eruptions. Interpretation of
zoning profile in minerals. Reconstruction of the crystallization history within
the magma chamber (RU-08).
68. Comparison between numerical models and data from other research units on
deformation field for further development of numerical models, with different
input parameters (UR-02);
69. Definition of the geometry of the potential decollement surfaces (UR-02);
70. Simulations of magma/rock dynamics with external triggers, and definition of
the expected geophysical signals (RU-08).
71. Refinement of the 3D FE model including anelastic rheologies. Application of
the 3D model predictions to the 2002-2003 and 2004-2005 activity (RU-08).
72. BEM modeling for simulation of relationships between pre-eruptive, eruptive
dynamics and superficial stress fields (UR-10);
73. Coulomb stress change maps on seismogenic structures (UR-11);
74. Numerical code for evaluating the thermoelastic deformation (UR-11);
75. FEM geodetic data inversion code (UR-11).
278
WP-4C) Analogue models
76. Interpretation and comparison of the analogue and the numerical experiments.
Quantitative comparison of the experiments to Etna (RU-01).
77. Definition of a general model of flank slip for Etna (all RUs involved in Task
4).
Task 5. Hazard
78. Seismic potential of faults: probabilities of occurrence of major earthquakes for
the given fault dataset (UR-04);
79. Seismic hazard maps in terms of macroseismic intensity for different exposure
times (5, 10, 20, 30 and 50 years) (UR-04);
80. Time-dependent seismic hazard maps (macroseismic intensity, exp. time 5, 10,
20, 30 and 50 years) (UR-04).
81. Map of distribution of the fracture and eruptive fissure systems of recent
volcanic events (UR-11).
WP-5C) Results for monitoring/surveillance activities
82. Integration of all the collected data and final volcano-structural hazard
evaluations (UR-11, with all RUs).
83. Prototypal procedures to be used by the Operations Centre of DPC in case of
unrest along the unstable flanks, highlighting possible hazard as a function of
the boundary conditions.
279
TABLE MAN/MONTHS
RU
RU-1
RU-2
Institutions
UniRm3,
Uni-Rm1,
Uni-Leeds
(UK),
Royal
Halloway,
London (UK)
Principal
Responsibles
Task1
Acocella,
Battaglia
@
@
Task2
Task3
@
Task4
Task5
Month/ p.
cofunded
@
@
44
@
@
35
UniMi,
Apuani,
UniMiB,
Tibaldi,
RU-3
CNR-ISMAR
Argnami,
@
RU-4
INGV-CT,
INGV-BO,
INGV-MI-PV,
Uni_Si, Uni-Ct,
CNR-IMATI
Azzaro,
Albarello,
Barbano,
Camassi,
D’Amico V.
@
RU-5
Uni-Rm1, UniCt,
Uni-Bo,
INGV-CT,
CNR-IGAG,
MBARI,
Monterey, USA
Chiocci,
Bosman,
Coltelli
@
@
35
RU-6
INGV-CT,
INGV-CNT,
Uni-Na, CSICMadrid, UniSavoie
Cocina, Patané,
Chiarabba, De
Gori, Got
@
@
57
RU-7
INGV-PA
Federico,
Favara, Gurrieri
@
@
RU-8
INGV-RM1,
INGV-CT,
INGV-OV,
Uni-Bo, ETH
Zurich,UCL
London
Giunchi,
Rovelli,
Vinciguerra,
Bonafede,
Bianco
@
RU-9
INGV-PI,
INGV-RM1,
Uni-Fi, Uni-Pi,
Univ.College
Dublin
Mazzarini,
Pareschi,
Pompilio,
Saccorotti,
Longo, Favalli
@
RU-10
Uni-CT, INGVCT
Nunnari
@
RU-11
INGV-CT, UniNA, Uni-Bo
Puglisi,
Bonaccorso,
Bonforte,
Branca, Burton,
Reitano
@
@
RU-12
UNI-BA
Siniscalchi,
Loddo
Schiavone
@
@
Total
@
@
@
@
@
requested
18
1
52
1 +19*
1 + 12*
20
@
@
72
2 + 9*
@
@
36
2
@
@
@
20
@
@
@
78
2
35
2
502
51
@
*Requested within the present Agreement, but not included within the Project cost statement
280
Mesi p.
Project V4 – FLANK. Financial Plan for the First Phase (Euros).
Finanziato dal
Dipartimento
b
Finanziato
dall'Organismo
c = a-b
1) Spese di personale
19850
0,00
2) Spese per missioni
74900
0,00
3) Costi amministrativi (solo per
Coordinatori di Progetto)
4) Spese per studi e ricerche ed altre
prestazioni professionali
168400
0,00
5) Spese per servizi
47100
0,00
6) Materiale tecnico durevole e di consumo
72970
0,00
7) Spese indirette (spese generali)
42580
0,00
425800
0,00
Categoria di spesa
Totale
Importo
previsto
a
0,00
Project V4 – FLANK. Financial Plan for the Second Phase (Euros).
Finanziato dal
Dipartimento
b
Finanziato
dall'Organismo
c = a-b
15850
0,00
59390
0,00
112300
0,00
16500
0,00
69830
0,00
30430
0,00
304300
0,00
Categoria di spesa
Totale
Importo
previsto
a
0,00
281
Project V4 – FLANK. Total Financial Plan, First + Second Phase (Euros).
Finanziato dal
Dipartimento
b
Finanziato
dall'Organismo
c = a-b
35700
0,00
134290
0,00
280700
0,00
63600
0,00
142800
0,00
73010
0,00
730100
0,00
Categoria di spesa
Totale
282
Importo
previsto
a
0,00
Project V4 –FLANK. Table RU’s and related funding request.
N. RU
RU-1
RU-2
RU-3
RU-4
RU-5
RU-6
RU-7
RU-8
RU-9
RU10
RU11
RU12
Istituz.
Resp UR
UNI-RM3
UNI-MI
CNR-BO
INGV-CT
UNI-RM3
INGV-CT
INGV-PA
INGV-RM1
INGV-PI
Acocella
Apuani
Argnani
Azzaro
Chiocci
Cocina
Federico
Giunchi
Mazzarini
UNI-CT
Nunnari
INGV-CT
Puglisi
Personale
Missioni
1st
2nd
1st
phase phase phase
8000
3400
1850 1850 3700
2500 2000 5000
5000
1000 1000 6000
3000
2600
8800
4400
3000 3000 9000
3000
3100
Studi,ricerche
Costi
e prestazioni
amministrativi
professionali
Servizi
Materiale
durevole
e di consumo
Spese
indirette
2nd
1st
2nd
1st
2nd
1st
2nd
1st
2nd
1st
2nd
phase phase phase phase phase phase phase phase phase phase phase
8000
17000 17000
6500 6500 3500 3500
3490
16600
6820 380 2980
430
3700
6800 8800
4300 2300 1850 1850
4000
12000 5000
3000 7000 2500 2000
5000
38600 12500 5000 5000 5400 2500
3000
16000
2500 4000 1950 5050 3050 1450
3000
10500 10500 1500 1500
5200
12000 4500
14400 11100 4400 2600
8000
23000 20000
5500 5000 4500 4000
3000
32000 32000
2900 12000 8000
13000 11000
1000
6000
1000
4000
4000
10000 15000 4900
4100
UNI-BA Siniscalchi
2500 8000 5000
20000 14000
4000 1000 4000 2500
4000
168400 112300 47100 16500 72970 69830 42580 30430
TOTAL 19850 15850 74900 59390
GRAND TOTAL:730100
283
284
Description of Research Units
285
286
Project V4 - FLANK
Hazard connected to the flank dynamics of Etna
RU V4/01
Scientific Responsible: Valerio Acocella, Researcher, Dipartimento Scienze Geologiche
Università Roma Tre, Largo S.L. Murialdo, 1, 00146, Roma. E-mail:
[email protected], tel: 06-57338043, fax: 06-54888201.
RU Composition:
Scientific Resp.
Position
Institution
Valerio Acocella
Researcher
Roma Tre
st
nd
Man/Months 1
phase
3
Man/Months 2
phase
3
Man/Months 1st
phase
1
2
3
Man/Months 2nd
phase
1
2
3
11
11
Participants
Position
Institution
Erika di Giuseppe
Gabriele Morra
Maurizio Battaglia
Gianluca Norini
PhD student
Post-doc
Associate
Professor
Post-doc
Univ. Roma Tre
Univ. Roma Tre
Univ. Roma La
Sapienza
Universidad de
Mexico
Marco Neri
Boris Behncke
Daniele Carbone
Researcher
Post-doc
Researcher
INGV Catania
INGV Catania
INGV Catania
0
0
0
0
0
0
Eleonora Rivalta
Post-doc
1
1
Agust
Gudmundsson
Riccardo Lanari
Full Professor
Univ. Of Leeds
(UK)
Royal Halloway,
London
CNR IREA,
Napoli
1
1
0
0
Senior researcher
Task 4
WP-4C) Analogue models.
The researchers participating to the Roma Tre UR will focus on the development of
analogue models of flank instability at Etna. When appropriate (e.g., to study the influence
of the development of mechanical and thermal porewater pressure on flank
destabilization), we will integrate the analogue models with analytical models. The two
main research problems that we will address in this part of project are (a) the identification
of the physical parameters controlling the stability of the volcano flanks and (b) the
threshold values of these parameters. Our aim is to understand the physics of these
processes, to be able to forecast they short and/or long term behavior.
The set up will be constrained from existing geophysical and geological data, in order to
produce models that are as close as possible to the natural case. In particular, the
distribution of the lithotypes characterizing the unstable flank (RUs of task 2B), as well as
287
their main mechanical and rehological properties (RUs of task 4A), will be considered
crucial input parameters for the models.
In general, this set of models is expected to use a cone of dry sand (Etna analogue)
and Newtonian silicone (magma or decollement analogue), accordingly with previously
proposed scaling procedures (Acocella, 2005, and references therein). The exact
rheological properties of these materials will depend upon the input parameters obtained
for the natural case. The influence of several factors (magma intrusion, topography,
regional tectonics, basal decollement, anisotropies within the cone, in collaboration with
the RUs from Tasks 2 and 3) will be considered to quantify the role of each of the factors
controlling the slip of the flank.
A few tens of models will be run, varying one parameter and maintaining the others
fixed each time. High resolution laser scanning of the surface of the experiments will
permit to appreciate the geometry and kinematics of the main structures characterizing the
deformation of the flank of the volcano analogue. The obtained experimental results will
be compared with the available field, bathymetric, seismic GPS and InSAR data (RUs of
task 2A and 2B), concerning the geometry and kinematics of the main structures and
portions of the unstable flank. This comparison will be aimed at studying and
understanding any similarity or difference between the observed and modelled geometric
and kinematic features of the unstable flank. Particular care will be given in evaluating the
mechanism of propagation of the slip of the unstable flank under extreme triggering events
(dike and/or magma emplacement).
The simulation of the development of mechanical and thermal fluid pressure due to the
intrusion of dikes is an additional, important process, which needs to be tested in the
experiments. Mechanically induced fluid pressures are controlled by non-dimensional
groupings of intrusion rate, dike thickness, fluid permeability, and hydraulic diffusivity of
the host rock, and fluid viscosity and overpressure. Thermally induced pore fluid pressures
are modulated by the differential magma temperature, bulk skeletal modulus, and thermal
expansion coefficient, with migration rates of the pressure pulse controlled by thermal and
fluid diffusivities. Most of these processes go beyond the ordinary modeling approach,
requiring an exceptional and challenging set-up and suitable materials. Moreover, severe
technical limitations in the planning and build-up of a proper apparatus are expected. For
these reasons, analogue models do not appear suitable, in terms of costs, available time and
benefits, to investigate these specific processes. To infer the relative importance of water
pressure, we will integrate and extend the analogue models with appropriate analytical
models (e.g., Ouyang et al., 2007; Brodsky and Kanamori, 2001; Elsworth and Day, 1999;
Delaney, 1982), applying to the analytical models the same initial and boundary conditions
of the analogue experiments. These models will be run in agreement with University of
Roma La Sapienza and Royal Halloway (London). Such a modeling is meant to represent a
significant step forward with regard to analogue models of volcano spreading previously
applied to Mt. Etna (Merle and Borgia, 1996).
The results from these models will be incorporated in the database of the project, in
the form of tables and diagrams, reporting the role of each parameter and the relationships
between parameters.
Contribute by the RU to the general Project products 1st year
1) Set up of Experimental apparatus.
2) Definition of the input parameters (in collaboration with RUs from Tasks 2B and
4a) and production of the experiments simulating flank slip. Set-up of the analytical
models.
288
Contribute by the RU to the general Project products 2nd year
1) Interpretation of the analogue and analytical experiments. Quantitative comparison
of the experiments to Etna (in collaboration with RUs of task 2A and 2B).
2) Definition of a general model of flank slip for Etna (in collaboration with the other
RUs).
Financial Request (in Euro)
First year
Categoria di spesa
Importo
previsto
a
Finanziato dal
Dipartimento
b
Finanziato
dall'Organismo
c = a-b
0,00
8000
0,00
17000
0,00
0,00
6500
0,00
3500
0,00
0,00
35000
0,00
Importo
previsto
a
Finanziato dal
Dipartimento
b
Finanziato
dall'Organismo
c = a-b
Totale
Second year
Categoria di spesa
0,00
8000
0,00
17000
0,00
0,00
6500
0,00
3500
0,00
35000
0,00
Totale
0,00
289
Total
Categoria di spesa
Importo
previsto
a
Finanziato dal
Dipartimento
b
Finanziato
dall'Organismo
c = a-b
0,00
16000
0,00
34000
0,00
0,00
13000
0,00
7000
0,00
70000
0,00
Totale
0,00
Curriculum of the Scientific Responsible
Valerio Acocella graduated in Earth Sciences at the University “La Sapienza” of Roma, in
1993. In 2000, he achieved a 4-years Ph.D. at the University of Siena. He is permanent
researcher in Structural Geology at the University of Roma Tre since 2006.
His main research interests include: relationships between tectonics and volcanism, at the
regional and local scale; pluton emplacement; active tectonics and fault interaction.
His main methodologies include: field analysis, analogue models, numerical models,
remote sensing.
The areas of main interest include: Italy (Ischia, Campi Flegrei, Vesuvio, Stromboli, Etna,
Vulsini, Amiata), Iceland, Ethiopian Rift and Afar, Taupo Volcanic Zone, NE Japan,
Kamchatka, Central Andes, Easter Island.
Valerio Acocella is author or co-author of 64 papers (55 published, 1 in press, 8 submitted)
on peer-reviewed journals, from 1999 to 2007. Of these, 57 are on international journals,
associated with a h-index = 14. Valerio Acocella is also author or co-author of 130
abstracts and extended abstracts related to presentations, mostly at international meetings,
from 1997 to 2007, of which 8 are solicited keynote lectures.
Valerio Acocella teaches “Volcano-Tectonics” (from 2007) and “Analogue Modelling”
(from 2002) at Roma Tre. In 2004 he has been visiting professor at the Graduate School of
Science, Tohoku University, Japan.
5 most relevant publications of RU
Acocella V. (2005) Modes of sector collapse of volcanic cones: insights from analogue
experiments.
Journal
of
Geophysical
Research, 110, B2, B02205,
doi:
10.1029/2004JB003166.
Acocella V. (2007) Understanding caldera structure and development: an overview of
analogue models compared to nature. Earth Science Reviews, 85, 125-160.
290
Acocella V., Behncke B., Neri M. D’Amico S. (2003) Link between major flank slip and
2002-2003 eruption at Mt. Etna (Italy). Geophysical Research Letters 30, 24, 2286,
doi: 10.1029/2003GL018642.
Neri M., Acocella V., Behncke B. (2004) The role of the Pernicana Fault System in the
spreading of Mt. Etna (Italy) during the 2002-2003 eruption. Bulletin of Volcanology,
66, 417-430. DOI: 10.1007/s00445-003-0322-x.
Battaglia M, Segall P., Roberts C.W. (1999) Magma intrusion beneath Long Valley caldera
confirmed by temporal changes in gravity. Science, 285, 2119-2122.
291
Project V4 - FLANK
RU V4/02
Scientific Responsible: Tiziana Apuani, Researcher, Dipartimento di Scienze della Terra “A.
Desio”, Università degli Studi di Milano, Via Mangiagalli 34, 20133 Milano, e-mail:
[email protected], tel: 0250315565, cell: 3387453092, fax: 0250315494
RU Composition:
Scientific Resp.
Position
Institution
Tiziana Apuani
Researcher
UNIMI
Man/Months 1st
phase
4
Man/Months 2nd
phase
4
Man/Months 2nd
phase
1
1
Participants
Position
Institution
Gianpaolo Giani
Giovanni Pietro
Beretta
Marco Masetti
Andrea Merri
Alessandro Tibaldi
Full Professor
Full Professor
UNIMI
UniMI
Man/Months 1st
phase
1
1
Researcher
PhD Student
Associate
Professor
Researcher
UNIMI
UNIMI
UNIMIB
1
3
3
1
3
2
UNIMIB
5
5
Claudia Corazzato
Task 4
WP-4A) Definition of the parameters
i) Main mechanical and rheological parameters of the lithotypes in the unstable flank.
In order to provide the dataset of the physical and mechanical properties of the volcanic
rock masses of Etna flank, representing one of the main input data for numerical
modelling, a geomechanical characterization of the involved rock masses will be
performed, and lithotechnical units will be defined. This will be done by integrating the
results of laboratory geotechnical and geomechanical tests already performed by our
research group and others on the same lithotypes, including also the extensive bibliography
now available on both volcanic and sedimentary deposits, with new data of rock mass
characterization. In the case that other research units dealt with laboratory characterization
of physical properties of Etna rocks, we will be ready to integrate also their data in our
models (second year of the project). The new rock-mechanical data will be systematically
collected in the eastern and south-eastern Etna flank, as well as in the sub-etnean clays,
through dedicated structural and geomechanical field surveys. The quantitative description
of representative rock masses, according to the International Society for Rock Mechanics
procedure (I.S.R.M., 1981), will comprise: number joint set, orientation, spacing,
persistence, roughness, well strength, aperture, filling, seepage of the main recognised
discontinuities, in order to evaluate the Rock Mass Rating value (RMR) (Bieniawski,
1989) and the Geological Strength Index (GSI) (Hoek et al., 2002). Those data will be
implement into the database (Task 1).
In the case that other research units dealt with laboratory characterization of physical
properties of Etna rocks, we will be ready to integrate also their data in our models (second
year of the project).
292
Stress-strain and stability analyses contribute to identify the critical conditions necessary to
generate instability at volcanoes, as well as the geometry of the failure surfaces, and
kinematics and size of unstable portions of the edifice, under different instability factors.
The numerical modeling will be performed using the bi- and tri-dimensional finite
difference geomechanical simulation codes FLAC and FLAC 3D (Itasca), that we already
successfully applied to Stromboli and other volcanoes. These codes assume a subdivision
of the mass in elementary cells, enable to include a wide range of information on both the
volcano and structures at their real scale and allow to choose appropriate constitutive laws.
They model a non-linear system evolving in calculation steps: the main advantage of this
analysis is that deformation and progressive failure can be recognised, plasticization areas
and creep deformation evidenced, geometry and volumes of the rock masses in critical
conditions identified.
The geological model used for the stress-strain numerical modelling focused at stability
analysis will incorporate data already existing on Etna, such as DEM, three-dimensional
distribution of main lithological units, seismic, structural and marine geology data,
hydrogeological features, as well as the complete geotechnical dataset of the physicalmechanical properties for the volcanic rock masses of Etna flank (§ 4.A i). The analyses
will include emerged and submerged slope, considering the role of groundwater and porewater pressures, on the base of the response of superficial and deep investigation carried
out by the Task 2 (WP-2A and WP-2B).
Bi and tri-dimensional stress-strain analyses of the eastern and south-eastern flank will be
performed to define the shallow and deep-seated slope deformation scenarios related to
different failure surfaces, as a response to different instability factors, whose role will be
evaluated. Pore-water pressurization will be considered as one of the possible triggering
factor for instability.
Particular interest will be posed in deformation induced by tectonic seismicity, pore
pressures increments, magmatic pressures associated to sheet intrusions with different
possible geometries, or a combination of these factors, taking into account the geological
framework of the involved units and the tectonic structures that affect the volcanic edifice
and its substrate. Limit Equilibrium methods will be also applied to initially explore
instability factors. A strong constrain on the results of modelling will be obtained thanks to
a continuous comparison with field data.
Through 2-D and 3-D numerical simulation, based as much as possible on field and
laboratory data, we will reconstruct the stress field of the main unstable sectors of the
eastern and south-eastern Etna flank, in relation with possible different hydrogeological
conditions, and/or magmatic intrusions into the volcanic edifice. This would also
contribute in understanding possible phenomena of passive magma rising along the main
N-S dyking zone of Etna.
The results of the proposed research program will contribute to the development of TASK
5, especially “5.B Integrated hazard – (iv) Volcanic-induced hazard related to flank slip,
including the effect on the rise and emission of magma; (v) Flank stability-induced hazard
related to fault activity, including the possible development of landslides; (viii) Suggestions
for any improvement of the monitoring system.
It will be possible to compare the results of our analyses with those obtained from the
INGV monitoring activity concerning the superficial deformations, e.g. radar
interferometry and geodesy (for which a close cooperation with the other research units is
293
expected), in order to validate geometries, causes and scenarios of instability, and supply
first indications for hazard assessment and monitoring advice.
1. Rock mechanical characterization of selected sites;
2. Physical and mechanical characterization of the main Etna lithotypes, and
definition of lithotechnical units;
3. First stress-strain numerical models of the unstable Etna flanks.
4. Comparison between numerical models and data from other research units on
deformation field;
5. Further development of numerical models, with different input parameters;
6. Definition of the geometry of the potential decollement surfaces;
7. Improved models of the eastern and south-eastern Etna flanks.
First year
Categoria di spesa
Importo
previsto
a
Finanziato dal
Dipartimento
b
Finanziato
dall'Organismo
c = a-b
3400
16600
,00
0,00
6820
,00
2980
,00
Totale
0,00
29800
Importo
previsto
a
Finanziato dal
Dipartimento
b
Second year
Categoria di spesa
294
Finanziato
dall'Organismo
c = a-b
0,00
3490
0,00
0,00
0,00
380
0,00
430
00
Totale
0,00
0, 430000
Importo
previsto
a
Finanziato dal
Dipartimento
b
Total
Categoria di spesa
Finanziato
dall'Organismo
c = a-b
0,00
6890
16600
,00
00
0,00
7200
00
3410
0
Totale
0,00
034100
Present position: Researcher (GEO/05), Dept. Earth Sciences, UNIMI. 1993: Graduated cum
laude in Earth Sciences, UNIMI. 1996: PhD in Engineering Geology, UNIMI. 1994-1995:
research at Imperial College of London, Centre for Engineering Geology. 1998-2000: post-doc
fellowship in Earth Sciences. 1998-2002: Professional engineering geologist; Assistant
Researcher in Engineering Geology, UNIMI and UNIMIB; CNR external collaborator.
Teaching: 1995-2005 Trainer, Engineering Geology, UNIMI. 2002-2007: Contract Professor,
Soil and Rock mechanics; UNIMI. Advisor/co-advisor of about 40 theses in Engineering
Geology. Published 25 scientific papers in nat./intern. peer-reviewed journals.
Research fields: geotechnical and geomechanical characterization of geomaterials; slope
stability analysis; numerical modelling. Current interest: Slope instability of active volcanoes
and related hazard: large flank collapses, debris flow phenomena; effect of hydrogeological
processes on slope stability.
Project coordination/participation: 2005-2007: coordinator of RU V2/17 (Milano) “Evaluation
of possible scenarios of deformation and dynamics of the Sciara del Fuoco” of the DPC-INGV
project V2. 2001-05: Thematic Leader of Rock and soil mechanics, geotechnics within
UNESCO-IUGS-IGCP project 455. 2000-2004: national GNV-INGV project “Stromboli
volcano hazard”, Milan RU “Reconstruction of the holocene deformation events of the Sciara
del Fuoco, Stromboli, and stability analysis” (coord. A. Tibaldi). Participation in several
geological researches for the control of slope instabilities: INTERREG III-A; CARIPLO
Valchiavenna Project; FIRST; GNDCI n. 21; IMONT INTERREG III-B “Alpine space”
295
Project ALPTER; IUGS-UNESCO-IGCP-Young Scientist n. 508, “Volcano collapse and fault
activity”; International Lithosphere Programme TASK II “New tectonic causes of volcano
failure and possible premonitory signals”.
1. Tibaldi A., Corazzato C., Apuani T., Cancelli A., 2003. Deformation at Stromboli
volcano (Italy) revealed by rock mechanics and structural geology. Tectonophysics,
361, 187-204.
2. Apuani T., Corazzato C., Cancelli A., Tibaldi A. 2005. Physical and mechanical
properties of rock masses at Stromboli: a dataset for flank instability evaluation.
Bulletin of Engineering Geology and the Environment, 64, 419-31, DOI
10.1007/s10064-005-0007-0.
3. Apuani T., Corazzato C., Cancelli A., Tibaldi A., 2005. Stability of a collapsing
volcano (Stromboli-Italy): limit equilibrium analysis and numerical modelling. Journal
of Volcanology and Geothermal Research, 144, 1-4, 191-210.
4. Apuani, T., Merri A., Masetti M., 2007. Effects of volcanic seismic events on the
Stromboli stability by finite difference numerical modelling, In: Malheiro A.M. and
Nunes J.C. (Eds.) Volcanic Rocks. Taylor & Francis, The Netherlands. 101-109.
5. Apuani T., Corazzato C., 2008. Numerical Model of the Stromboli Volcano (Italy)
Including the Effect of Magma Pressure in the Dyke System. Rock Mechanics and
Rock Engineering, in press.
296
Project V4 - FLANK
RU V4/03
Scientific Responsible: Andrea Argnani, Senior Researcher, ISMAR-CNR, Via Gobetti
101, 40129 Bologna, email: [email protected], tel: 051-6398886, fax: 0516398940
RU Composition:
Scientific Resp.
Position
Institution
Andrea Argnani
Senior Researcher
ISMAR-CNR
Participants
Position
Institution
Claudia Bonazzi
Marzia Rovere
Co.Co.Co.
Art. 23
ISMAR-CNR
ISMAR-CNR
Man/Months 1st
phase
3
Man/Months 2nd
phase
3
Man/Months 1st
phase
4
2
Man/Months 2nd
phase
5
2
Task 2
Several lines of evidence suggest that the submarine flank of Mt. Etna has been the site of
extensive gravity failure processes, operating at various scales; in some instances, very
scale scale slumps and slides can be observed. The relative chronology of these events
need to be unravelled, as well as their age with respect to the formation of the Valle del
Bove.
Key questions are:
i) what is the evolution in time of these extensive mass wasting deposits?
ii) how do these gravity failure events relate to the activity of the volcano?
iii) is there a deep tectonic drive to mass wasting on the eastern flank of Mt. Etna?
iii) how do these gravity failure events relate to the formation of the Valle del Bove?
An extensive data set of multichannel seismic reflection profiles, belonging to the RUs
V4/03 and V4/09, is now avalable to study the gravity failure events on the submarine flak
of Mt. Etna. Preliminary inspection to the seismic profiles of the various data sets suggests
that the areal extent and thickness of the various gravity failure deposits can be mapped
with some accuracy. This, in turn, should allow attempting to answer the questions
presented above.
WP-2A) Surface
Map with the traces of all the available marine seismic profiles, together with multibeam
morphobathymetric data, as a starting point. Two sets of medium to high resolution
multichannel seismic profiles acquired by ISMAR will be used for this study and
integrated with a set of seismic profiles acquired by the PISA-INGV R.U. The main
tectonic structures will be identified and correlated, in order to place them on a map.
Special attention will be drawn on the distribution of the large-scale mass transport
deposits already reported on the offshore flank of Mt. Etna (Argnani and Bonazzi, 2005;
Pareschi et al., 2006, GRL33, L13302). This large-scale gravity failure has been related to
297
a particularly large eruptive event, but it could also represent the superficial response of a
deeper collapse of the volcano flank. A comparison between the mass wasting deposits
identified through seismic profiles and the detailed multibeam morphobathymetry can be
particularly useful in order to assess the subsequent modification (erosion) operated by
bottom currents on the deposits.
WP-2B) Depth
A stratigraphic framework will be obtained by correlating the seismic units identified on
seismic profiles, and the main tectonic structures will be also identified and correlated. The
distribution in depth (in seconds, TWT) of the major fault planes will be highlighted. A
map showing the distribution and thickness (in seconds, TWT) of the mass wasting
deposits will be also prepared. Assessment of the relative age of the tectonic structures and
of main sedimentary units and attempt to correlate the sedimentary deposits to stratigraphic
units whose age is known, in order to build a chronology that allows a comparison with the
events affecting Mt. Etna on land.
If appropriate, depth conversion of key seismic profiles will allow to estimate a realistic
depth geometry of the tectonic structures, besides allowing a more accurate estimate of the
volume of the mass wasting deposits. The depth geometry of the tectonic structures located
near the Etna edifice can allow to check the eastward extent of the decollement surfaces
inferred to occur underneath the collapsing eastern flank of the volcano. It is worth noting
that the grid of seismic profiles that will be used for this study extends from the Messina
Straits to the Hyblean offshore, allowing a regional interpretation of the tectonic structures.
Such a large-scale overview can be particularly useful in order to outline which fault
patterns are due to regional tectonics and which may be related to Mt. Etna volcanotectonics, and can help assessing how the two patterns eventually interfere.
The tectonic and morphological features presented on the structural maps will contribute
to the GIS Data Base (Task 1). In particular, a map containing the tracks of multichannel
seismic profiles and of all the geological data obtained from seismic interpretation will be
prepared together with RU V4/09. We expect to be able to map the regional tectonic
structures, areal extent and thickness of the major gravity failure deposits, and structural
features related to gravity failure. The data will be also organized in a Geographical
Information System.
Finally, the structural geometry obtained from seismic profiles can offer additional
constraints for numerical and analogue modelling (Task 4) and for hazard assessment
(Task 5).
1. Assemblage of available data, mostly marine seismic profiles, on working maps.
2. Work on seismic data in order to identify and correlate the main
seismostratigraphic units.
3. Identification and correlation of the main tectonic structures on seismic profiles.
4. Mapping the distribution of the large-scale mass-wasting deposits located offshore
the eastern flank of Mt. Etna.
5. Build up of a relative chronology of tectonic activity and stratigraphic events.
6. Attempt of correlation of the identified seismic units to stratigraphic units of known
age located onshore.
298
1. Mapping of fault surface with depth on seismic profiles in order to outline fault
geometry.
2. Interpretation of tectonic structures at a large scale, in order to outline the fault
patterns which are due to regional tectonics and the patterns which may be related
to Mt. Etna volcano-tectonics, and eventually assessing how the two patterns
interfere.
3. Depth conversion of selected seismic profiles in order to obtain a realistic geometry
of fault planes and a more accurate volume estimate of the mass-wasting deposits
located on the offshore flank of Mt. Etna. Fault geometry can be used as input for
analogue and numerical modelling.
4. Tectonic model describing the deformation affecting the offshore flank of Mt. Etna
within the regional tectonics of the area.
First year
Finanziato dal
Dipartimento
b
Finanziato
dall'Organismo
c = a-b
1850
0,00
3700
0,00
6800
0,00
Categoria di spesa
Importo
previsto
a
0,00
4300
0,00
1850
0,00
0,00
18500
0,00
Importo
previsto
a
Finanziato dal
Dipartimento
b
Finanziato
dall'Organismo
c = a-b
1850
0,00
3700
0,00
8800
0,00
Totale
Second year
Categoria di spesa
0,00
299
2300
0,00
1850
0,00
0,00
18500
0,00
Importo
previsto
a
Finanziato dal
Dipartimento
b
Finanziato
dall'Organismo
c = a-b
3700
0,00
7400
0,00
15600
0,00
Totale
Total
Categoria di spesa
0,00
6600
0,00
3700
0,00
37000
0,00
Totale
0,00
Personal Details:Andrea Argnani, born on 18th September 1958 in Faenza (Italy), is
currently senior research scientists at ISMAR-CNR, Bologna, where he has been working
for the last 20 years, participating in about 20 research cruises. His main duties concern: i)
interpretation of geophysical data; ii) planning of marine geophysical surveys; iii) regional
geological syntheses; iv) structural geology, tectonics and geodynamics of the
Mediterranean area; v) kinematic and palaeogeographic reconstructions of the
Mediterranean region; vi) basin evolution and dynamics; vii) subsidence analysis. The
principal Lines of Research cover: i) Seismo-tectonics and tsunamigenic potential of
active tectonic structures in the Italian Seas, with special reference to the peri-Garganic
region, Eastern Sicily offshore, the Messina Straits and the Aeolian Islands; ii) Tectonics
and kinematics of the Mediterranean region from Mesozoic to Present; iii) Crustal-scale
tectonics of the northern Apennines and Po Plain: geodynamic implications and
neotectonics; iv) Tectonics of the African foreland; v) Tectonics and magmatism of the
Tyrrhenian backarc basin; vi) Palaeomagnetism and tectonics of the northern Apennines.
In the last 10 years he has been working on the following Research Projects: a) Scientific
coordinator of the Research Programme “The Taormina Fault and surroundings:
geophysical investigation”, DPC-INGV 2004-2006, Progetto S2, coord. D. Slejko and G.
Valensise. b) Scientific coordinator for the Marine Geological Sheets (subsurface geology)
Venezia, Ancona, Pescara, Vieste and Bari within the Project "Cartografia Geologica
Marina 1 : 250.000", APAT. c) 2000 - 2004: Scientific coordinator the Research
Programme GNDT Programma Quadro 2000-2002 “Evaluation of Geological Hazards in
the Seas around Italy”.
300
Argnani A., Serpelloni E., C. Bonazzi C. (2007) - Pattern of deformation around the central
Aeolian Islands: evidence from GPS data and multichannel seismics. Terra Nova, 19,
317-323..
Serpelloni E., Vannucci G., Pondrelli S., Argnani A., Casula G., Anzidei M., Baldi P.,
Gasperini P. (2007) – Kinematics of the Western Africa-Eurasia plate boundary from
focal mechanisms and GPS data. Geoph. J. International, 169, 1180-1200.
Argnani A. (2006) - Some Issues Regarding the Central Mediterranean Neotectonics. Boll.
Geofisica Teorica Applicata, 47, 13-37.
Argnani A. and Bonazzi C. (2005) - Tectonics of Eastern Sicily Offshore. Tectonics, 24,
TC4009, doi:10.1029/2004TC001656, 2005.
Vannucci G., Pondrelli S., Argnani A., Morelli A., Gasperini P. and Boschi E. (2004) - An
Atlas of Mediterranean Seismicity. Annali di Geofisica, suppl. vol. 47, 247-306.
301
Project V4 - FLANK
RU V4/04
Scientific Responsible: Raffaele Azzaro, Senior Researcher, Istituto Nazionale di
Geofisica e Vulcanologia-Sezione di Catania, Piazza Roma 2, 95123 Catania, email:
[email protected], tel: 095-7165821, fax: 095 435801
RU Composition:
Scientific Resp.
Position
Institution
Azzaro Raffaele
Senior Researcher
INGV-CT
Participants
Albarello Dario
Barbano Maria S.
Camassi Romano
Position
Institution
Man/Months 1st
phase
3
Man/Months 2nd
phase
3
Man/Months 1st
phase
0.5
1
1
Man/Months 2nd
phase
0.5
1
1
Associate Professor UNI-SI
Associate Professor UNI-CT
Senior
INGV-BO
Technologist
Castelli Viviana
Researcher
INGV-BO
2
1
D’Amico Vera
Researcher
INGV- MI-PV
0.5*
0.5*
D’Amico Salvatore Researcher
INGV-CT
4
4
Maiolino Vincenza Researcher
INGV-CT
5
5
Musacchio Gemma Researcher
INGV-MI-PV
2
2
Peruzza Laura
Researcher
INOGS-TS
1
2
Privitera Eugenio
Senior Researcher
INGV-CT
3
3
Rotondi Renata
Senior Researcher
CNR IMATI-MI
2
2
Tuvè Tiziana
Researcher
INGV-CT
9*
9*
Zonno Gaetano
Senior Researcher
INGV-MI-PV
2
2
Task 1
All relevant dataset used for the analyses proposed hereinafter (e.g. historical earthquake
catalogue) and results produced in cartographic form (strain release maps, hazard maps
etc) will be available in a geo-referred format to be inserted into GIS system.
Task 3
WP-3A) Long term
A wide analysis on the pattern of long term seismicity in the volcano’s eastern flank will
be developed in order to investigate relationships with eruptive activity and flank
instability processes in a significantly long time-span (ca. the last 400 years). The research
will include the following points:
Improvement of the seismological dataset. The aim of this activity is to extend the 18322005 macroseismic catalogue of Mt. Etna earthquakes (Azzaro et al., 2000; 2002; 2006) as
far back 1600s, period in which large eruptions occurred. The investigation will be made
by exploring the a number of historical sources such as: i) seismological and
volcanological literature; ii) bibliographic and historiographic studies, repertories and
302
periodicals available for the area; iii) non-local repertories (journalistic sources and diaries)
chosen for their high informative potential. According to the methods and procedures of
the historical seismology (Camassi and Castelli, 2004), the collected information will be
classified and then critically analyzed to obtain the intensity data of the studied
earthquakes. Finally, each event will be parameterized (magnitude, epicentre etc) so that
the portion of the catalogue prior to 1832 may be compiled with the same criteria and
format of the existing directory. It must be stressed that the recent Italian seismic
catalogues (Camassi and Stucchi, 1997; Gruppo di Lavoro CPTI, 2004) cannot be used for
obtaining an organic picture of Etnean seismicity and investigating the evolution of the
sequences, since they adopt magnitude thresholds and space-time windows inappropriate
(events occurring within ± 30 km and ± 90 days with respect to a stronger shock are
discarded).
Fault behaviour. The analysis is aimed to characterize the behavior of the active faults in
the eastern flank over a centennial period. Although the occurrence of strong earthquakes
both during some flank eruptions (e.g. 1865, 1879, 1911, 2002) or independently may be
apparent from the catalogue, the seismic activity of some faults appears almost regularly
clustered and alternated between them during time, with a sort of return period. After a
validation of the seismotectonic model (Azzaro, 2004) – most of the structures appear
segmented into sections ruled by seismic, stick-slip behavior or continuous, stable-sliding
creep – and the association earthquake-causative fault (from evidence of coseismic surface
faulting and damage distribution), the study will focus on style of the seismic release
shown by single seismogenic structures or set of them (grouped for homogeneous seismic
zones if data are not sufficient) located in the eastern sector of the Mt. Etna.
Seismotectonic features and fault behavior will be investigated through the reconstruction
of the curves of seismic strain release and b value, and the verification of occurrence
models possible (time or slip predictable, variable slip, characteristic earthquake, etc).
Moreover, Montecarlo simulations will be performed in order to obtain synthetic
earthquake catalogues that can be associated to the faults; this method is very promising to
integrate the experimental sample for a good estimate of statistical properties, like mean
recurrence time and its intrinsic variation. All these analyses are expected to indicate how
much faulting processes may be related with eruptive dynamics (emplacement/intrusion of
dykes) or geodynamic processes at a larger scale (instability of the eastern flank, offshore
tectonics).
Task 5
WP-5A) Seismic hazard
Seismic potential of faults. The Timpe tectonic system has been responsible for most of the
largest earthquakes occurred in the Etna region during the last 200 years (e.g. S. Tecla fault
in 1865, 1914; Moscarello f. in 1865, 1911 etc). Even if the magnitudes of these very
shallow shocks did not exceed 4.9, destruction were not rare (on average every 20 years)
and intensities in the epicentral area reached values up to degree X EMS. Local
communities living in the eastern flank, the most densely urbanized sector of the volcano,
continuously suffer social and economic losses due to the very high occurrence frequency
of damaging earthquakes, usually neglected in the hazard assessment practice at a national
scale. A contribute for detailed mapping of the more hazardous zones is represented by the
characterization of the seismic potential of all the active faults occurring in the eastern
sector of the volcano. This feature will be investigated through three different methods.
Deterministic approach: the maximum expected magnitude is obtained i) by the calculation
303
of b value of the Gutenberg-Richter relationship, and ii) on the basis of the fault dimension
(field data from Tasks 2 and 3A) through a relationship specifically derived for the Etna
region, as already done in New Zealand (the relationship by Well and Coppersmith, 1994
is inadequate for volcanic areas). iii) Probabilistic assessment of the magnitude expected in
different exposure times (5, 10, 20, 30, 50 years).
Relationships of intensity attenuation. In volcanic areas the intensity decay (∆I) and its
variation as a function of the epicentral distance is still a crucial problem for seismic
hazard estimates. In this project computation of ∆I in the Mt. Etna area will be faced
through two probabilistic techniques based on methods by Rotondi and Zonno (2004;
2006) and Magri et al. (1994). Both the approaches will produce relationships to assess the
probability distribution of the intensity value at a site, given the epicentral intensity and the
site-epicenter distance. We will try to analyze the attenuation pattern also taking the source
effect into account (different attenuation trends with respect to the azimuth of the source).
The relationships will be used for the computation of seismic hazard at the site (see point
below).
Seismic hazard assessment. A first probabilistic seismic hazard assessment (PSHA)
recently carried out in the Mt. Etna region, indicates that the ‘local’ events represent a
significant source of hazard when short exposure times are considered (Azzaro et al.,
2008). The analysis, carried out in the framework of the previous project S1-DPC, has
been performed using a numerical procedure based on the extensive use of local
macroseismic information (Albarello and Mucciarelli, 2002). With this aim, the software
‘SASHA’ (D’Amico and Albarello, 2007) has been also developed. In practice, this
method uses the seismic histories to the site (i.e. the record of the observed/calculated
intensities at a given locality) to estimate the probability of exceedance of an intensity
value in different exposure times. In the present project, our purpose is to provide a
detailed mapping of the more hazardous zones of the eastern flank of the volcano by using
the extended historical earthquake database (see Task 3A), the new probabilistic
relationships of intensity attenuation (see point above), and investigating the effects of
different exposure times in the estimations. In particular, starting from the exposure time of
50 years (in a Poissonian model it corresponds to a return period of 475 years), that is used
as a standard in the calculations of the national seismic hazard map (MPS Working Group,
2004), the analysis will be extended to shorter exposure times (5, 10, 20 and 30 years) to
quantify the contribution of local seismogenic sources and/or site effects in influencing the
pattern of the seismic hazard in the area. Since the inhomogeneous distribution of inhabited
centers around the volcano, the hazard maps will be represented as continuous data on a
grid with a step of 1 km, in which each node represents the expected intensities with 10 %
probability of exceedance in a given number of years. On the other hand, as seismic hazard
estimates are expected to be differently influenced by the time elapsed since the last event,
time dependent approaches will be also applied to some well-known structures of the
Timpe fault system. Following the experience of the previous project S2-DPC on the
national scale, the analysis will be based on a renewal model using the Brownian Passage
Time (BPT) distribution, and results compared with those obtained with the stationary
assumption. Finally, according to several historical cases occurred in the eastern flank, we
propose to study the aspect of fault interaction by static stress re-distribution (i.e. Stein,
1999). If the increase or decrease in static stress is followed by a variation in the seismic
rate (by a time-dependent recovery), then the estimation of seismic hazard will be strongly
influenced.
304
1.
2.
3.
4.
Extension of the macroseismic catalogue from ≈1650 to 1831.
Analyses on fault behavior: strain release and b value.
Seismic potential of faults: deterministic approaches.
New probabilistic relationships of intensity attenuation.
1. Analyses on fault behavior: occurrence models, Montecarlo simulations of
earthquake catalogues.
2. Seismic potential of faults: probabilities of occurrence of major earthquakes for the
given fault dataset .
3. Seismic hazard maps in terms of macroseismic intensity for different exposure
times (5, 10, 20, 30 and 50 years).
4. Time-dependent seismic hazard maps (macroseismic intensity, exp. time as above).
5. Static stress simulations.
First year
Finanziato dal
Dipartimento
b
Finanziato
dall'Organismo
c = a-b
2500
0,00
5000
0,00
12000
0,00
Categoria di spesa
Importo
previsto
a
0,00
3000
0,00
2500
0,00
0,00
25000
0,00
Importo
previsto
a
Finanziato dal
Dipartimento
b
Finanziato
dall'Organismo
c = a-b
2000
0,00
4000
0,00
Totale
Second year
Categoria di spesa
305
5000
0,00
0,00
7000
0,00
2000
0,00
0,00
20000
0,00
Importo
previsto
a
Finanziato dal
Dipartimento
b
Finanziato
dall'Organismo
c = a-b
4500
0,00
9000
0,00
17000
0,00
Totale
Total
Categoria di spesa
0,00
10000
0,00
4500
0,00
45000
0,00
Totale
0,00
Scientific activity
(1) Studies aimed at recognising seismogenic faults and defining their behaviour by the
analysis of long-term seismicity. Active tectonics in the volcanic region of Mt. Etna using
earthquake surface faulting, fault creep and paleoseismology. Seismotectonic and
geodynamic modelling.
(2) Historical investigations on large and moderate earthquakes occurred in the region;
compilation of seismic catalogues and databases using macroseismic data, parametrization
of historical earthquakes.
(3) Probabilistic seismic hazard assessment using intensity data; evaluation of damage
scenarios from seismic history analyses.
Coordination activity
(1) Responsible for RU’s of projects funded by the Dipartimento di Protezione Civile:
• S1, upgrade and management of the seismic hazard map of Italy (2004-06);
• EDURISK, educational activities for mitigating seismic and volcanic risks (2002-04,
2004-06);
(2) Coordinator of the INGV working groups:
• TTC 5.1, Data Base and macroseismic methods;
• EMERGEO and QUEST, post-earthquake surveying teams for geological and
macroseismic effects.
306
Azzaro R. (2004) – Seismicity and active tectonics in the Etna region: constraints for a
seismotectonic model. American Geophysical Union, Geophysical monograph, 143, “Mt.
Etna: volcano laboratory”, A. Bonaccorso, S. Calvari, M. Coltelli, C. Del Negro and S.
Falsaperla (Eds.), 205-220.
Azzaro R., Barbano M.S., D'Amico S., Tuvè T., Albarello D. and D'Amico V. (2008) –
First studies of Probabilistic Seismic Hazard Assessment in the volcanic region of Mt.
Etna (Southern Italy) by means of macroseismic intensities. Boll. Geof. Teor. Appl., 49,
15 pp., in print.
Camassi R and Castelli V. (2004) – Looking for "new" earthquake data in the 17th-18th
century European "newssellers" network. J. Earth. Engineering, 8 (3), 335-359.
Pace B., Peruzza L., Lavecchia G., and Boncio P. (2006) – Layered Seismogenic Source
Model and Probabilistic Seismic-Hazard Analyses in Central Italy. Bull. Seism. Soc. Am.,
96, 107-132.
Rotondi R. and Zonno G. (2004) – Bayesian analysis of a probability distribution for local
intensity attenuation. Ann. Geophys., 47, 5, 1521-1540.
307
Project V4 - FLANK
RU V4/05
Scientific Responsible: Francesco Latino Chiocci, Full Professor, Dipartimento Scienze
della Terra, Università di Roma “La Sapienza”, P.le A. Moro, 5 – 00185 Roma. e-mail:
[email protected], tel.: 06/49914938, 06/44585075 fax: 06 4454729
RU Composition:
Scientific Resp.
Position
Institution
Chiocci Francesco
L.
Full Professor
University of
Rome La Sapienza
Participants
Position
Institution
Coltelli M.
Cavallaro D.
First Researcher
PhD Student
Casalbore
PhD Student
Fascetti A.
Contract Research
Bosman A.
Clague D.
Researcher
Senior Scientist
INGV – Catania
University of
Catania
University of
Bologna
University of
Rome La Sapienza
CNR - IGAG
MBARI,
Monterey, USA
Man/Months 1st
phase
1
Man/Months 2nd
phase
2
Man/Months 1st
phase
1
5
Man/Months 2nd
phase
1
5
5
5
3
3
2
0
2
0
Task 2
WP- 2A) Surface
Activity 1) A direct correlation between tectonic/large-scale instability feature onshore and
offshore will be realized, by using a) very high resolution swath bathymetry (HRSB)
collected in the framework of DPC-IGV V3_6 project; b) geological mapping of the
onshore coastal sector; c) scuba dives on specific targets in shallow water (<50m) selected
on HRSB data; d) ROV dives on specific targets in deeper water (>50m) selected on
HRSB data.
As already evident from the ongoing analysis, the structural framework of the coastal area
could be fully re-interpreted on the basis of the offshore morpho-structural setting. There
are, in fact, well detectable active fault systems, offsetting the seafloor of several meters up
to some tens of meters. What were previously interpreted as separate structural trends
could be re-interpreted as part of a same system, related to the large-scale instability of the
volcano eastern flank. Gas seepage would be testified, if the interpretation of mud
volcanoes on the shallow offshore of the Pernicana fault will be confirmed by direct
observation and sampling.
Activity 2) On the Etna offshore two oceanographic cruises were ruled out on 2006 and
2007. The results are extremely interesting, as the main structural domains were defined on
the basis of the morpho-structural setting and deep water tectonic/large-scale instability
feature were detected. Despite some 20 seafloor dredging were performed in the last cruise
308
and some more were realized in the past (1997 and 1999) by IIV-CNR, still most of the
interpretation based on the morpho-structural setting have to be validated, in order to
achieve a robust interpretation of the main tectonic unit building up the continental margin
(thrust chain, foredeep, shield volcano, ..). Therefore an oceanographic cruise will be
realized (possibly onboard of R/V Universitatis) to dredge and core the main morphostructural domains, with special emphasis on shield volcano, Chiancone, Riposto Ridge, as
well as of a depositional terrace whose presence (or absence) will be used to constrain the
recent tectonic activity of the different coastal sectors. All the geophysical data and
seafloor sampling collected in the past will be integrated. Collaboration with other unit will
be realized as well.
1. Map of integrated (on shore and off-shore) structural features (1:50.000 scale).
2. Map of selected features (1:10.000).
3. Integration of all data available in shallow water (scuba observations, HR seismic
data, HRSB, grab and core samples, side scan sonar sonographs).
4. Report on scuba and ROV survey on selected targets (if it will be possible, we will
perform part of this activity during the first year).
5. Report on the oceanographic cruise with the R/V Universitatis.
1. Map of the data collected in both previous surveys and first-year survey.
2. Report on scuba and ROV survey on selected targets.
3. Characterization of the nature of possible mud volcanoes in the offshore Pernicana
Fault.
4. Mapping and characterization of the tectonic elements cropping out on the coastal
zone (on land and offshore).
5. Analysis of samples collected in the first-year cruise, and of all the geophysical
data collected.
6. Interpretation of the off-shore structural elements and of tectonic/large-scale
instability features possibly driving the movement of the eastern flank of the
volcano.
First year
Categoria di spesa
Importo
previsto
a
Finanziato dal
Dipartimento
b
0,00
5000
Finanziato
dall'Organismo
c = a-b
0,00
0,00
38600
0,00
309
5000
0,00
5400
0,00
Totale
0,00
54000
Importo
previsto
a
Finanziato dal
Dipartimento
b
Second year
Categoria di spesa
Finanziato
dall'Organismo
c = a-b
0,00
5000
0,00
0,00
12500
0,00
5000
0,00
2500
0,00
Totale
0,00
25000
Importo
previsto
a
Finanziato dal
Dipartimento
b
Total
Categoria di spesa
Finanziato
dall'Organismo
c = a-b
0,00
10000
0,00
0,00
51100
0,00
10000
0,00
7900
0,00
Totale
0,00
79000
Full Professor at University of Rome “La Sapienza” since 2004., Born in Gubbio, 22 08
1959, Degree in Geology (110 with honours) and PhD in Earth Sciences at University of
Rome “La Sapienza”. Researcher at National Research Council (CNR) from 1988 to 1998,
Associated Professor at University of Rome from 1998 to 2004.
310
Participated to some 40 oceanographic cruises (half of them as chief scientist) mainly in
the Tyrrhenian Sea but also in the Red Sea, Atlantic and Pacific Oceans and Antarctica.
Chief Scientist on a EC-funded cruise to use TOBI deep-sea vehicle in the Tyrrhenian Sea
(EASS Program).
200-2006 Co-Leader of IGCP (International Geologic Correlation Program) Project #464
“Continental shelves during last glacial cycle. Knowledge and applications”.
2007-2011 Co-Leader of IGCP (International Geologic Correlation Program) Project #524
“Risk, Resources and Record of the Past on Continental”.
Project leader of MaGIC, a 5-year project (2007-2011) for mapping geohazards on the
shelves/slopes of the Italian Coasts.
Project Leader of PRIN project (2006-2008) on coastal landslide in Calabria
Scientific Director or Project Manager of geological mapping (1:50.000) of marine areas of
7 geological sheets.
Participates to European Projects TRANSFER (Tsunami Risk in European Seas) and
BEACHMED (Beach Nourishment of retreating sandy coastlines).
Member until 2006 of INGV steering committee of volcanological projects (involving
some 1000 researchers).
Co-Leader of a three-year (2000-2002) GNV National Project to study instability on the
flanks of Italian volcanic islands. In charge, for the National Civil Protection Agency, of
the researches for causes and consequences of the submarine landslide that caused a
tsunami wave in Stromboli on Dec.2002. Responsible of a 2 year research (2005-2007) to
study instability features on Etna volcano submerged flank.
Is in charge of search of relict sand on continental shelves to be used for beach
nourishment on long-term projects funded by Regione Lazio (1999-2007), Regione
Abruzzo (2000-2003) Regione Toscana (2005-2007) and Regione Basilicata (2005-2006).
Responsible of bi-lateral projects with Morocco (2004-2007) and Spain (1998-2000).
Is responsible of one of the five study areas of the National Project VECTOR (2006-2008)
to study the impact of future environmental changes on the Italian coasts.
Chiocci F.L., Martorelli E., Bosman A. (2003) Cannibalization of a continental margin by
regional scale mass wasting: an example from the central Tyrrhenian Sea. In: Submarine
Mass Movements and Their Consequences, J Locat and J. Mienert Eds., Kluver
Academic Publisher, 409-416.
D. Casas, H. Lee, G. Ercilla, Kayen R., Estrada F., Alonso B., Baraza J., Chiocci F.L:
(2004) "Sedimentary, geotechnical and physical characterization of the continental slope
and basin of the Bransfield Peninsula (Antarctic Peninsula)” Marine Georesources and
Geotechnology, 22 (4): 253-278
Tommasi P., Baldi P:, Chiocci F.L., Coltelli M., Marsella M., Pompilio M. Romagnoli C.
(2005) The landslide sequence induced by the 2002 eruption at Stromboli volcano.
Landslide - Risk analysis and sustainable disaster management, chapter 32: 251-258,
Springer Verlag
Chiocci F.L. and de Alteriis G. (2006) The Ischia debris avalanche: first clear submarine
evidence in the Mediterranean of a volcanic Island pre-historic collapse. Terra Nova 18
(3):
Chiocci F.L., Romagnoli C., Bosman A. (2008) Morphologic resilience and depositional
processes due to therapid evolution of the submerged Sciara del Fuoco (Stromboli
Island) after the December 2002 submarine slide and tsunami. Geomorphology, in press
311
Project V4 - FLANK
RU V4/06
Scientific Responsible: Ornella Cocina, Researcher, Istituto Nazionale di Geofisica e
Vulcanologia-Sezione di Catania, Piazza Roma 2, 95123 Catania, email: [email protected],
tel: 095-7165836, fax: 095-435801
RU Composition:
Man/Months
1st phase
2
Man/Months 2nd
phase
3
Institution
Man/Months
1st phase
Man/Months 2nd
phase
INGV-CT
Dept de
volcanologia,
CSIC, Madrid
INGV-CT
INGV-CNT
1
1
1
1
2
1
3
1
2
1
3*
1
2
1
3*
1
3
3
2
3*
6
2
3*
6
Scientific Resp.
Position
Institution
Ornella Cocina
Researcher
INGV-CT
Position
Salvatore Alparone
Carmen Martinez
Arevalo
Researcher
Researcher
Graziella Barberi
Claudio Chiarabba
Pasquale De Gori
Salvatore Gambino
Elisabetta Giampiccolo
Jean Luc Got
Researcher
Senior
Researcher
Researcher
Technologist
Researcher
Lectures
Vadim Monteiller
PhD student
Antonino Mostaccio
Carla Musumeci
Adriano Nobile
Technician
Researcher
PhD student
Participants
Domenico Patanè
INGV-CNT
INGV-CT
INGV-CT
Universitè de
Savoie
Universitè de
Savoie
INGV-CT
INGV-CT
University of
Napoli
INGV-CT
Senior
1
1
Researcher
Salvatore Spampinato
Senior
INGV-CT
3
3
Researcher
Andrea Ursino
Researcher
INGV-CT
2
2
Task2
WP-2B) Depth
In order to provide new insights into the relationship between the shallow feeding system
of the volcano and the dynamic behavior of its eastern sector the aim of the task is i) to
model the velocity and attenuation structure in the investigated area, through the
application of passive tomography techniques and ii) to perform a detailed analysis on the
seismogenetic structures located in the eastern flank, by mean of high precision locations
of “families” of seismic events.
312
Recent velocity and attenuation tomographic studies (Patanè et al., 2006, De Gori et
al.2005), performed during pre-eruptive and eruptive period, evidenced that the strongest
anomalies are mostly located in the central and eastern sectors of the volcano. Besides the
recognition of anomalies related to the magma intrusion, during the last recent lateral
eruptions (2001 and 2002-2003), the tomographic inversions highlight high Vp/Vs and low
Qp volumes in the eastern flank, whose interpretation is still debated (high fracturing,
presence of melt, fluid migration).
The stages in which the research will be undertaken are the following:
a) Data analysis: accurate 1D locations of the seismicity recorded during two selected
time period will be performed. The first period is related to the 2003-2004 time
interval, to investigate both on the velocity and attenuation structure before and during
the 2004 summit eruption. The second dataset is related to June-November 2005 time
period, during which a passive seismological experiment was carried out on the
volcano. During this period a temporary array of 23 digital broad-band seismic stations
were deployed around the volcano and near its top to integrate the permanent seismic
network. The installation of additional instruments, the use of broad-band 3-component
sensors, and more accurate arrival time picks will allow us to improve the spatial
resolution and the sharpening of the imaged structure during this time interval.
b) Velocity tomography: to define the 3D velocity structure we will firstly apply
SIMULPS code, which calculate the Vp and the Vp/Vs models (Thurber 1993,
Eberhart-Phillips, 1993 e Eberhart-Phillips e Reyners, 1997). The results will be
compared to those obtained applying another technique, related to the Double
Difference method using the finite difference scheme (Podvin and Lecomnte, 1991)
and the Tarantola-Valette approach (Monteiller et al., 2005) to compute the velocity
structure.
c) Attenuation Tomography: The definition of the Qp attenuation structure of the study
area will integrate the informations coming from the velocity tomographic inversions.
Being the attenuation a physical parameter sensitive to the thermal state of crust
volumes through which the seismic waves travel, the joint analysis of Qp, Vp and
Vp/Vs models will allows us to better constrain the physical parameters of the Mount
Etna plumbing system, in order to better identify local strong lateral heterogeneities
and/or fluid –filled cracked volumes.
d) High precision locations: The application of double difference techniques in the
velocity tomographic study, will produce more accurate relative event locations,
improving the spatial clustering of the seismicity. In order to better characterize the
seismogenic structures in the eastern flank of the volcano, we intend to perform
detailed analysis on the “families of events” just recognized by the 3D locations. The
proposed technique will be based on the re-location of “multiplets” performed using a
cross-spectrum method.
1. Data analysis.
2. 1D Vp and Vp/Vs models.
3. Starting of the Vp, Vp/Vs, Qp, Qs 3D inversions.
1. 3D numerical models of P- and S- wave velocities to be used for earthquake
locations.
2. 3D numerical models of Qp and Qs.
313
3. Precise locations on selected clusters occurring nearby seismogenic structures.
4. Database of locations relative to the period 2003-2004, including the 2004 summit
eruption.
First year
Finanziato dal
Dipartimento
b
Finanziato
dall'Organismo
c = a-b
1000
0,00
6000
0,00
16000
0,00
2500
0,00
1950
0,00
3050
0,00
0,00
30500
0,0031
Importo
previsto
a
Finanziato dal
Dipartimento
b
Finanziato
dall'Organismo
c = a-b
1000
0,00
3000
0,00
Categoria di spesa
Totale
Importo
previsto
a
Second year
Categoria di spesa
0,00
4000
0,00
5050
0,00
1450
0,00
14500
0,00
Totale
314
0,00
Total
Finanziato dal
Dipartimento
b
Finanziato
dall'Organismo
c = a-b
2000
0,00
9000
0,00
16000
0,00
6500
0,00
7000
0,00
4500
0,00
45000
0,00
Categoria di spesa
Totale
Importo
previsto
a
0,00
Ornella Cocina was born in Catenanuova (EN) l’11.02.1963. In January 1989, she
graduated in Earth Sciences at the University of Catania. From April 1989 she leads
seismological researches at IIV_CNR, now Istituto Nazionale di Geofisica e Vulcanologia
(INGV) - Sezione di Catania and collaborates to the sourveillance activity carried out by
this Institute. The research arguments mainly regarded space-time-energy distribution of
the seismic activity, space-time characterization of the seismic stress and strain tensors,
with particular reference to the variations of the local stress fields induced by magmatic
source. In the last years she directed her researches to tomography studies with the aim to
contribute to the knowledge of the internal dynamics of the Etna volcano and in
particular, on its feeding systems. Different techniques of seismic tomography have been
applied, to investigate on the space-time distribution of the seismic wave velocity under
Mt. Etna.
Patanè D., Barberi G., Cocina O., De Gori P.and Chiarabba C. (2006). Time-Resolved
Seismic Tomography Detects Magma Intrusions at Mount Etna. Science, 313, 821-823.
De Gori P., Chiarabba C., Patanè D. (2005). Qp structure of Mount Etna: Constraints for
the physics of the plumbing system. J. Geoph. Res., 110, B05303,
doi:10.1029/2003JB002875.
Martinez-Arevalo C., Patanè D., Rietbrock A., Ibanez M. J. (2005) – The intrusive process
leading to the Mt. Etna 2001 flank eruption: Constraints from 3-D attenuation
tomography. Geoph. Res. Lett.,32, L21309, doi: 10.1029/2005GL023736.
Chiarabba C., De Gori P., and Patanè D. (2004) - The Mt. Etna Plumbing System: The
contribution of Seismic Tomography, In: Mt. Etna Volcano: A Seismological
Framework, in. Mt. Etna: Volcano Laboratory, Eds. Bonaccorso et al., AGU, Geophys.
Monograph, 143.
315
Patanè D., Chiarabba C., Cocina O., De Gori P., Moretti M, Boschi E. (2002) Tomographic images and 3D earthquakes locations of the seismic swarm preceding the
2001 Mt. Etna eruption: Evidence for a dyke intrusion. Geoph. Res. Lett., 29, 10,
doi:10.1029/2001GL014391.
316
Project V4 - FLANK
RU V4/07
Scientific Responsible: Cinzia Federico, Researcher, Istituto Nazionale di Geofisica e
Vulcanologia, Sezione di Palermo, via Ugo La Malfa 153, 90146 Palermo, email:
[email protected], tel: 091-6809493, fax: 091 6809449.
RU Composition:
Man/Months 1st
phase
3
Man/Months 2nd
phase
3
INGV-PA
Man/Months 1st
phase
2
Man/Months 2nd
phase
2
INGV-PA
INGV-PA
INGV-PA
INGV-PA
INGV-PA
INGV-PA
INGV-PA
1
0
2
0
1
0
1
1
0
2
0
1
0
1
INGV-PA
0
0
Scientific Resp.
Position
Institution
Cinzia Federico
Researcher
INGV-PA
Participants
Position
Institution
Rocco Favara
Director of
Research
Senior Researcher
Researcher
Technologist
Researcher
Technologist
Researcher
Researcher
Researcher
Sergio Gurrieri
Fabrizio Nigro
Marco Liuzzo
Sofia De Gregorio
Andrea Rizzo
Marco Camarda
Ester Gagliano
Candela
Fabio Pisciotta
Task 1.
Available geochemical data (water chemistry, CO2 fluxes) will be put together in a GIS
system, together with the shape and depth of the sedimentary basement.
Task 2
WP-2A) Surface
Volcanic fluids upraise along preferential pathways within the volcanic edifice, namely
faults and geometric discontinuities.
The activities planned for this task are:
- the identification of surface anomalies of gas flux, through real-time gas flux monitoring,
and geometric constraints of gas-aquifer interaction
WP-2B) Depth
The definition of the volume of aquifers, characterized by peculiar mass rate and
permeability, is needed for the comprehension of the relationships between gas ascent and
gas (CO2) entrapment in groundwater. In this context, the sedimentary basement represents
the base of the volcanic aquifer and the interface between two media with different
physical characteristics.
The activities planned for this subtask are:
317
-
-
-
the definition of the geometry of the sedimentary basement, through available
stratigraphic and geophysical data, and eventual supplementary measurements. The
expected accuracy is about 50 m.
definition of the volume and yield of the different aquifers hosted within the volcanic
edifice, through the geometrical computation based on the sedimentary basement
surface, the digital elevation model of the volcano, the modeling of the piezometric
surface.
identification of hydrological basins and main drainage directions
possible definition of the deeper extent of the faults, based on the configuration and
features of the water flow within the aquifer(s).
Task 3
WP-3B) Short term (1993-2004, monitoring data)
The geochemical investigations carried out in the last 10 years on gases discharged
from the peripheral areas of Mount Etna allowed to assess the absolute degassing pressure
of such emissions as well as to identify magma transfers within the deep feeding system.
Shallow magma degassing has been also observed and monitored through some anomalous
soil gas discharges located on the volcano flanks, in order to follow magma rise from depth
toward the surface. A significant portion of CO2 and water vapor is likely trapped during
ascent in the aquifer hosted within the more permeable levels of the volcanic edifice, and
its effect on shallower manifestations should be better investigated. Gas emissions directly
rising along central conduits were recently monitored real-time, and gave clear insights
into volcanic dynamics during either eruptive or non-eruptive phases.
Fluids permeating volcanic edifices (water, volcanic gases), besides the magma itself,
deeply affect the mechanical properties of rocks and, even more, the variations of the pore
fluid pressure are frequently released as rock failure, earthquakes and permeability
variations, which in turn affect fluid movement, with a feedback mechanism. This, in turn,
can have some effects on the stability of some portions of the volcanic edifice, due to the
stress-induced failure of rocks. Indeed, fluid pore pressure is frequently considered as the
cause of a kind of seismicity and can crucially affect slope stability.
The activity planned for this task concern the
- Analysis of available geochemical dataset, in term of spatial distribution of measured
parameters and temporal variations in relation with the eruptive dynamics during recent
volcanic activity.
- Measurements of the piezometric level in some selected wells
- the modeling with appropriate software of fluid circulation (gas and water) in the
volcanic edifice, and their pattern within the volcanic edifice; the structural model of the
volcano, obtained from activities ascribed to Task 1, will be translated to a grid for further
simulations;
- the modeling of the effect of pore pressure on characteristics of volcanic rocks (porosity
and permeability);
The surface effects of past volcanic activity, observed in geochemical parameters, will be
tentatively simulated by changing mass rate and pressure of fluids at depth.
1. Definition of the physical characteristics of the volcanic rocks.
2. Physical model of the volcano, with the identification of the zones of different
permeability.
318
3. Preliminary simulations of fluid circulation.
1. Vertical and spatial distribution of main fluid pathways.
2. Simulation of the effect of the variation of the fluid mass rate and/or pressure on
shallow. geochemical manifestations during past volcanic activity.
3. Simulation of the effects of fluid mass rate and/or pressure on rock characteristics.
4. Simulation of the effects of fluid mass rate and/or pressure on rock characteristics
(porosity and permeability)
1° year
Categoria di spesa
Importo
previsto
a
Finanziato dal
Dipartimento
b
Finanziato
dall'Organismo
c = a-b
0,00
3000
0,00
0,00
0,00
10500
0,00
1500
0,00
0,00
15000
0,00
Importo
previsto
a
Finanziato dal
Dipartimento
b
Finanziato
dall'Organismo
c = a-b
Totale
2° year
Categoria di spesa
0,00
3000
0,00
0,00
0,00
10500
0,00
1500
0,00
15000
0,00
Totale
0,00
319
Total
Categoria di spesa
Importo
previsto
a
Finanziato dal
Dipartimento
b
Finanziato
dall'Organismo
c = a-b
0,00
18000
0,00
0,00
0,00
9000
0,00
3000
0,00
30000
0,00
Totale
0,00
Cinzia Federico born in Collesano (PA) on 1st April 1970. In 2000 she had the PhD in
Geochemistry and since then she worked at the INGV-PA as researcher. She is the
scientific responsible of the geochemical surveillance of Mt. Vesuvius.
Her research interests concern the study of volcanic plumes in relation with the volcanic
activity, through discrete and real-time measurements of acidic gas species. Furthermore,
she focused on hydrological systems in volcanic areas (Mt. Vesuvius, Stromboli, Mt.
Etna), and particularly on the interaction of volcanic gases with groundwaters and their
effect on water chemistry. In this frame, she also studied the behavior of trace elements in
volcanic aquifers and processes of gas-water-rock interaction. She also studied soil
degassing as a tool to identify faults in volcanic areas, and mechanisms of gas transport in
soils.
From 2003 to 2006 she has been the scientific responsible of partnership INGV-Regione
Piemonte for the monitoring of seismicity in this part of Northern Italy.
She is co-author of about twenty-five articles published in international scientific journals.
Aiuppa, A., Moretti, R., Federico, C., Giudice, G., Gurrieri, S., Liuzzo, M., Papale, P.,
Shinohara, H., Valenza, M., 2007. Forecasting Etna eruption by real time evaluation of
volcanic gas composition. Geology, 35, 12: 1115-1118, DOI: 10.1130/G24149A.1
Aiuppa A., C. Federico, G. Giudice, S. Gurrieri, M. Liuzzo, H. Shinohara, R. Favara, M.
Valenza (2006) Rates of carbon dioxide plume degassing from Mount Etna volcano. J.
Geophys. Res., 111, B09207, doi:10.1029/2006JB004307
Aiuppa, A., Federico, C., Giudice, G., Gurrieri, S., Paonita, A., Valenza, M. (2004) Plume
chemistry provides insights into the mechanisms of sulfur and halogen degassing at
basaltic volcanoes. Earth Planet. Sci. Lett. 222(2), 469-483.
Aiuppa, A., Federico, C. (2004) Anomalous magmatic degassing prior to the 5th April 2003
paroxysm on Stromboli. Geophys. Res. Lett., 31, L14607, doi:10.1029/2004GL020458.
320
Federico C., Aiuppa A., Allard P., Bellomo S., Jean-Baptiste P., Parello F. and Valenza M.
(2002) Magma-derived gas influx and water-rock interactions in the volcanic aquifer of
Mt. Vesuvius, Italy. Geochim. Cosmochim. Acta, 66, 963-981.
321
Project V4 - FLANK
RU V4/08
Scientific Responsible: Carlo Giunchi, Senior Researcher, Istituto Nazionale di Geofisica
e Vulcanologia, Sezione di Sismologia e Tettonofisica, Via di Vigna Murata 605, 00143
Roma, email: [email protected], tel: 0651860411, fax: 0651860507.
RU Composition:
Scientific Resp.
Position
Institution
Carlo Giunchi
Senior Researcher
INGV-RM1
Participants
Position
Institution
Sergio Vinciguerra
Antonio Rovelli
Maurizio Bonafede
Spina Cianetti
Emanuele Casarotti
Giuseppe Di Giulio
Fabrizio Cara
Giovanna Calderoni
Marta Pischiutta
Giuliano Milana
Francesca Bianco
Lucia Zaccarelli
Susanna Falsaperla
Horst Langer
Luciano Scarfì
Piero Del Gaudio
Piergiorgio Scarlato
Andrea Cavallo
Luigi Burlini
Luca Caricchi
Philip Meredith
Michael Heap
P. Baud
Researcher
Researcher
Professor
Researcher
Researcher
Researcher
Researcher
Researcher
Ph.D Student
Technologist
Senior Researcher
Researcher
Senior Researcher
Researcher
Researcher
Tecnologist
Senior Researcher
Researcher
Senior Researcher
Post Doc
Professor
Ph.D Student
Lecturer
Man/Months 1st
phase
2
Man/Months 2nd
phase
2
Man/Months 1st
phase
2
2
1
2
1
6
6*
2
1
2
2
1
2
2
2
1
1
1
1
1
1
1
1
Man/Months 2nd
phase
3
2
1
2
1
3
3*
2
1
2
2
1
2
2
2
1
1
1
1
1
1
1
1
INGV-RM1
INGV-RM1
UNI-BO
INGV-RM1
INGV-RM1
INGV-RM1
INGV-RM1
INGV-RM1
INGV-RM1
INGV-RM1
INGV-OV
INGV-OV
INGV-CT
INGV-CT
INGV-CT
INGV-RM1
INGV-RM1
INGV-RM1
ETH, Zurich
ETH, Zurich
UCL, London
UCL, London
IPG,
Strasbourg
Task 3
Earthquakes of the eruptive periods of July 2001 and October 2002 were recorded by local
broad-band stations installed in and around Catania for microzonation purposes. Two of
them were deployed on the SE flank of Mt. Etna. Moreover, two accelerographs of RAN
(National Accelerometric Network) recorded on scale the strongest events of October
2002. All these data offered an unprecedented opportunity revealing the presence of a
significant long-period (LP) ground motion component during the most damaging events.
The excess of low-frequency amplitude (with a spectral peak around 3 s) causes large
322
displacements, of the order of those typical of M ≈ 6 for tectonic earthquakes (Milana et
al., 2008). Therefore, shallow depth may not be the unique cause for the high damage of
volcanic events of Mt. Etna, large ground displacements implying large drift ratio, i.e. the
ratio between the maximum top displacement and the building height.
LP earthquakes are intrinsically related to the flank dynamics and represent the most
crucial contribution to seismic hazard in the Mt. Etna area. A thorough study is planned
including the correlation between the eruptive processes and the occurrence of LP
earthquakes, the waveform scaling, and the determination of the cause of the large lowfrequency motions with particular attention to the role of depth and focal mechanism.
Moreover, long continuous recordings of broad-band local stations before, during, and
after the seismic swarms offer the opportunity for a study of volcanic tremor variations in
concomitance with the occurrence of LP earthquakes. In principle, the role of fluids can
affect predominant frequency variations both for volcanic earthquakes and tremor, and
local continuous recording are the most useful tools to confirm this hypothesis detecting
frequency variations in the noise structure.
Also polarization of earthquakes and ambient noise along the major faults of Mt. Etna can
give important insight on the volcano structure and attenuation of earthquake effects.
Dense ambient noise measurements have already been performed on the Tremestieri,
Pernicana, Acicatena and Moscarello faults (Rigano et al., 2008). These measurements will
be extended to the other faults of Mt. Etna.
The relationship between ground motion polarization and anisotropy has been
hypothesized (Rigano et al., 2008) but has to be demonstrated yet. Earthquake waveforms
recorded so far at portable stations run for temporary experiments on Mt. Etna can be
analyzed to infer information on local anisotropy looking at the S-wave splitting,
comparing ground motion polarization with fast velocity directions. Moreover, controlled
source experiments and laboratory tests will be performed to put experimental constraints
to azimuthal variations of velocity and attenuation in dependence on the local fracture field
and crack orientation. Chemical shots will be blast in the Pernicana fault area and recorded
at 2D arrays of 20 broad-band stations. Samples representative of in situ stress conditions
will be obtained by drilling boreholes at depths up to twenty meters. Elastic wave
velocities (both P and S waves) will be measured along the three main directions at
increasing effective pressure, in order to quantify the textural and the voids space seismic
anisotropy. Measurements will be carried out both for dry and fluid saturated samples, in
order to take into account the effects of fluids for attenuation and fluid transmissivity.
Measurements will be carried out at HP-HT Laboratory, INGV Rome. The joint analysis of
this data will allow to quantitatively support the seismological observations carried out and
the edifice geophysical properties. Moreover, a detailed study of attenuation of seismic
energy including azimuthal variations is an important tool in the hazard assessment.
References:
Milana, G., A. Rovelli, A. De Sortis, G. Calderoni, G. Coco, M. Corrao, and P.
Marsan (2008). The magnitude of damaging volcanic earthquakes of Mt. Etna: why the
commonly used magnitude scales are not adequate, Bull. Seism. Soc. Am. (submitted).
Rigano, R., F. Cara, G. Lombardo, and A. Rovelli (2008). Evidence for ground motion
polarization on fault zones of Mt. Etna volcano, J. Geophys. Res. (submitted).
323
Task 4 – Modeling
WP-4A) Definition of parameters
Mechanical parameters, such static and dynamic elastic moduli, uniaxial compressive
strength are crucial for the definition of stress-strain relationships. Mechanical parameters
are needed for ground deformation modeling, as well as for the modeling of the weakening
mechanisms destabilizing the volcano eastern sector. We selected the two most
representative lithologies in order to understand their mechanical and rheological behavior
and provide quantitative parameters for the large-scale instability of the eastern flank: the
extrusive basalt from the lava flows and the Plio-Pleistocene clays. Samples will be
collected at selected quarries. The experimental work will aim to define 1) physical
properties of the lithologies (density, porosity, dynamic elastic moduli, seismic anisotropy
of both P and S wave at room pressure); 2) mechanical parameters, such as static elastic
moduli and uniaxial compressive strength; 3) P and S wave velocities under increasing
effective pressure and temperature for the lava flows, representative of the edifice stress
conditions.
Even if the study of pore P under deformation is beyond our objectives and would require a
suite of triaxial deformation laboratory experiments, we will run uniaxial compressive tests
on water saturated samples and we will explore the weakening effects on the compressive
strength. On the same token, we can explore in the permeameter, how pore pressure
increases under increasing hydrostatic pressure. If time and resources will be left, we might
run a few pilot deformation tests in triaxial deformation apparata, in order to have first
insights on the evolution of pore P under deformation.
Main tests carried out
1) Uniaxial compressive strength at room pressure and temperature and bench P and S
elastic waves velocities for the Plio-Pleistocene clays.
2) P and S elastic waves velocities for lava flows at increasing effective pressure (up to 300
MPa and 1200°C)
Main facilities
1) Uniaxial testing machine with double loading cell (15 and 250 kN) and deformation
control.
2) Permeameter for simultaneous P, S and fluid permeability at effective pressures up to
100MPa
3) Paterson rig apparatus, load cell 1000kN, effective pressures up to 300MPa and
temperatures up to 1200°C and PZT transducers for the physical properties
4) WD/ED Microprobe (5 spectrometers) JEOL JXA 8200
5) Field Emission Electron Microscope JEOL JSM 6500 F
Mount Etna has been extensively monitored in the last decade by geodetic and satellite
techniques (GPS, leveling, EDM, InSAR) providing a fairly detailed description of the
deformation both during quiescent and active phases. The period ranging between 1993
and 2005 is characterized by multiple inflation-deflation phases caused by feeding of the
reservoir system and consequent eruption, followed by a renewed feeding regime and by a
new eruption: these phases are somehow coupled to the seismic activity along tectonic,
well-known, structures and to the instability of the eastern flank of the volcano.
324
Our purpose is to investigate, by a large-scale 3D finite element model, the cause-effect
relationship occurring between volcanic and seismic activity and how this can be linked to
the E flank instability. We plan to include in the full model of the volcanic edifice all the
major potential sources (surface dikes or buried pressurized cavities), the most significant
seismogenic structures with realistic frictional properties (such as Pernicana and the
Mascalucia-Tremestieri-Trecastagni fault systems) and the rheological discontinuities
(clay-basalt interface). Additionally there is strong evidence that the elastic rheology,
usually assumed in modeling volcanic deformation, is a crude and inaccurate assumption
for Mount Etna. For example the time-delay observed between volcanic inflation/eruption
and the seismic activity along the major fault systems suggests that a time-dependent
rheology is necessary to model this interaction. Last but not least, the thermal anomalies
characterizing the volcanic areas are responsible for the anelastic behavior especially in
proximity of the sources. We want to include this effect in the FE model using a plastic
rheology whose yield stress can be function of stress and/or temperature.
The solid modelling of Mount Etna is a complex task, that will be approached using recent
software specifically developed to allow us the reconstruction of topography, internal
conformation of geologic structures and structural discontinuities. Sensitivity analysis of
the 3D discretization will be performed to evaluate the stability of the numerical method as
a function of the assumed rheology and of the discontinuities geometries.
1.
2.
3.
4.
5.
6.
Microstructural characterization of the natural lithologies investigated.
Uniaxial compressive strength (room pressure and temperature).
Static and dynamic elastic moduli (room pressure and temperature).
Definition of Secondary seismic anisotropy (Voids space+texture).
Preliminary 3D FE model of of the unstable flanks of Mt. Etna.
Study of the role of different sources (summit eruptions, deep pressurized
reservoirs, regional tectonic stress) on the structural discontinuities and flank
instability.
1.
2.
3.
4.
5.
6.
7.
Dynamic elastic moduli for lava flows at increasing effective pressure.
Microstructural characterization of the experimental products.
Definition of Primary seismic anisotropy (Texture).
Map of directions of polarization.
Attenuation of volcanic LP earthquakes.
Refinement of the 3D FE model including anelastic rheologies.
Application of the 3D model predictions to the 2002-2003 and 2004-2005 activity.
325
First year
Finanziato dal
Dipartimento
b
Finanziato
dall'Organismo
c = a-b
4400
0,00
8800
0,00
12000
0,00
Categoria di spesa
Importo
previsto
a
0,00
14400
0,00
4400
0,00
1111112110,0
0
44000
1210,00
Importo
previsto
a
Finanziato dal
Dipartimento
b
Finanziato
dall'Organismo
c = a-b
2600
0,00
5200
0,00
4500
0,00
Totale
Second year
Categoria di spesa
0,00
11100
0,00
2600
0,00
0,00
26000
0,00
Importo
previsto
a
Finanziato dal
Dipartimento
b
Finanziato
dall'Organismo
c = a-b
7000
0,00
14000
0,00
Totale
Total
Categoria di spesa
326
16500
0,00
0,00
25500
0,00
7000
0,00
70000
0,00
Totale
0,00
Carlo Giunchi (born in 1965) has a permanent position at INGV since 1999. He is Senior
Researcher since 2003. After the degree in Physics at the University of Bologna in 1991,
he gets the PhD in Earth Sciences at the University of Milano in 1998. He takes part in
various MIUR, UE and DPC project since 1998. His research topics range from subduction
dynamics and postglacial rebound to fault interactions and mantle and lithosphere
rheology. In recent times he is studying the inference of volcanic deformation sources
using geodetic data. He is author of 25 papers in peer-reviewed journals and more than 50
abtracts to international meetings.
Stanchits S., Vinciguerra S., Dresen G. (2006). Ultrasonic velocities, Acoustic emission
characteristics and crack damage of basalt and granite, Pure Applied Geophysics, 163,
1-20..
Vinciguerra S., Trovato C., Meredith P.G., Benson P.M. (2005). Relating seismic
velocities, permeability and crack damage in interpreting the mechanics of active
volcanoes, International Journal of Rock Mechanics, 42/7-8, 900-910.
Bianco, F. , L. Scarfì, E. Del Pezzo and D. Patanè (2006). Shear wave splitting changes
associated with the 2001 volcanic eruption on Mt. Etna, Geophys. J. Int., 167, 959-967,
DOI: 10.1111/j.1365-246X.2006.03152.x
Bonaccorso, A., Cianetti S., Giunchi C., Trasatti E., Bonafede M., Boschi E. (2005).
Analytical and 3-D numerical modelling of Mt. Etna (Italy) volcano inflation. Geophys.
J. Int., 163, 852- 862, doi: 10.1111/j.1365-246X.2005.02777.x
Trasatti, E., C. Giunchi, and N. Piana Agostinetti (2008). Numerical inversion of
deformation caused by pressure sources: application to Mount Etna (Italy). Geophys. J.
Int., 172, 873-884, doi: 10.1111/j.1365-246X.2007.03677.x
327
Project V4 - FLANK
RU V4/09
Scientific Responsible: Francesco Mazzarini, Researcher, Istituto Nazionale di Geofisica e
Vulcanologia-Sezione di Pisa, Via della Faggiola, 32 - 56126 Pisa, email:
[email protected], tel: 050 8311956, fax: 050 8311942
RU Composition:
Scientific Resp.
Position
Institution
Francesco
Mazzarini
Researcher
INGV-PI
Man/Months 1st
phase
3
Man/Months 2nd
phase
3
Man/Months 2nd
phase
2
Participants
Position
Institution
Maria Teresa
Pareschi
Massimo Pompilio
Gilberto Saccorotti
Paola Del Carlo
Antonella Longo
Massimiliano
Favalli
Simone Tarquini
Ilaria Isola
Marina Bisson
Luca Bisconti
Chiara Montagna
Melissa Vassalli
Andrea Cassioli
Michele Barsanti
Andrea Cavallo
Massimo Tiepolo
Chris Bean
Gareth O’Brian
Marco Neri
Director of
Research
Senior Researcher
Senior Researcher
Researcher
Researcher
Senior Researcher
INGV-PI
Man/Months 1st
phase
2
INGV-PI
INGV-PI
INGV-CT
INGV-PI
INGV-PI
3
2
3
0
0
3
2
3
0
0
Technologist
Technologist
Technologist
Researcher
Ass. ricerca
Ass. ricerca
PhD Fellow
Researcher
Technologist
Researcher
Ass. Professor
PhD Fellow
Researcher
INGV-PI
INGV-PI
INGV-PI
INGV-PI
INGV-PI
INGV-PI
Univ. Firenze
Univ. Pisa
INGV-RM
IGG-CNR-PV
Univ. Coll. Dublin
Univ. Coll. Dublin
INGV-CT
0
0
0
0
0
0
1
2
0
1
1
1
0
0
0
0
0
0
0
1
2
0
1
1
1
0
Task 1
The dynamics of spreading and flank instability/failure at Mount Etna is mainly driven by
the load of the volcanic pile/edifice over the basement, the basement structure and
mechanical stratigraphy (i.e. occurrence of basal detachments), and the activity of the
volcanic system (i.e. feeders, shallow level magmatic chambers, conduit dynamics and
eruptive events). In a such a complex scenario one question is pivotal for both civil
protection and science issues: what is the link between the seismicity/tectonics, the flank
instability and the volcanic activity at Mount Etna? To fully answer such a complex
question a multi-disciplinary approach and geological, volcanological, petrological and
geophysical data necessitate. Among the variety of investigations this UR aims to face the
following three points: a) to perform a numerical simulation of the dynamics of a
328
magmatic/rock system when affected by i) new arrival of magma in the shallow system
and ii) the possible trigger of eruption by the occurrence of external perturbation
(earthquakes and/or landslides); b) to perform petrological and mineralogical analysis on
the volcanics erupted from Mount Etna to gain information on the thermal and barometric
pre- and syn eruptive state of magma in the volcanic system; c) to make a contribution in
defining the relationships between the regional tectonic structures and the flank instability
of the eastern sector of Mount Etna by analysing off-shore seismic lines. All the results
deriving form the activities described below will be stored into a data-base incorporated
into a GIS environment based on ESRI ArcView (ArcGis) software.
Task 2- Geometry, kinematics and structure of the “unstable” flanks
WP-2B) Depth
What are the actual relationships between the seaward spreading of the eastern and southeastern sectors of Mt. Etna and the huge amount of mass wasting deposits off-shore? In
order to make some contribution to this problem initially all the available literature data
about the on-shore and off-shore tectonic structures in the eastern and south-eastern Mount
Etna flanks as well as in the Ionian Sea will be critically analysed. A critical evaluation of
literature data on the extent of submarine mass-wasting deposits (landslides) will be also
carried out. A base-map of the main faults and submarine landslides will be thus compiled
in order to provide a geographic platform over which all the interpretations of the new
seismic lines will be placed. Multi-channel high resolution 2D seismic data (sampling at 1
s, record length of 3 s TWT) acquired on May 2005 off-shore of Catania will be elaborated
and interpreted to better define: i) the possible relationships between landslides and faults;
ii) the off-shore extent of the fault zones bordering north and south the seaward spreading
of the eastern flank of the volcano. The definition of the relationships between the
landslides deposits off-shore Mt. Etna, probably testifying for an episode of flank
instability, and the fault could provide some clues on the relative timing of flank instability
and tectonic activity. The seaward spreading of the eastern flank of the volcano is bordered
by fault zones. The southern border of the eastern flank is marked by folds and faults (e.g.
Mascalucia and Trecastagni) whereas the northern border is marked by the Pernicana fault.
Most of the off-shore bulging is comprised between the off-shore continuations of these
two fault zones. By analyzing selected seismic lines passing across the site of the possible
off-shore continuation of the Pernicana fault and the Mascalucia Trecastagni faults we will
define which fault system pass trough the volcanic pile and continue into the crust and
which one simply affects only the volcanic pile. The results will be compared and
integrated with other off-shore seismic data aimed at investigating the crustal strain at
regional scale in collaboration with other research units (e.g. CNR-Bologna) in order to
provide a consistent geologic/structural scenario for the instability and the seaward
spreading of the Mount Etna eastern and south-eastern flanks.
Task 4- Modelling
WP-4A) Definition of parameters
A petrologic study of products erupted during relevant eruptions of Mt Etna will be carried
out in order to 1) estimate pre-eruptive conditions in terms of pressure, temperature and
chemico-physical properties of magma 2) recognize effects of changes/perturbations
occurring within the plumbing system (depth, volume of magma reservoir, recharge rate)
on solid-liquids-gas equilibria; 3) find a relation with the flank dynamics (gravity and
329
tectonics) of the volcano. Results will provide inputs for numerical simulations carried out
within the same RU and in the same time they will contribute to the validation and refining
of the above models. Products of eruptions representative of different styles, magnitude
and intensities will selected, with a particular attention to those more recent events
observed by a complete multidisciplinary monitoring system (e.g. after 1995). Beside a
basic textural and compositional study, which includes petrography and bulk rocks
analyses, detailed chemical analyses of minerals and glasses will be performed in order to
recover pre-eruptive conditions. The database of experimental-determined phase equilibria,
produced during the previous DPC-project, will be employed in order to increase accuracy
of estimates resulting from generic thermodynamic models. A special care will be devoted
to interpret chemical zoning of those minerals (e.g. plagioclase) whose growth/dissolution
rate is strongly dependent on processes of degassing, decompression and magma chamber
refilling. Detailed zoning profiles will be obtained by a combination of high resolution
BSE images, X-ray elemental maps and spot analyses carried with electron microprobe and
laser ablation ICP-MS techniques and will be employed to reconstruct the pre-eruptive
crystallization history. . The latest multi-component models for lava parameters (e.g.
viscosity, density) will be taken into account in the modelling.
WP-4B) Numerical models.
Numerical simulations of the dynamics of the magmatic and rock system at Mount Etna
will be performed with the aim of i) understanding the magma dynamics during the preeruptive phases accompanying and following the arrival of gas-rich magma into the
shallow system; ii) evaluating the possible role of external perturbations (earthquakes or
landslides) in triggering magma convection and pressurization; iii) estimating the timespace dependent gravity, deformation and seismic signals produced by the simulated
dynamics. System conditions for the simulations in terms of chamber/conduit geometries
and depth, magma composition and temperature, etc. will be defined by the project
consortium, including the investigation carried out by this same RU, in order to be
representative of relevant conditions for Mount Etna. Numerical simulations of magma
dynamics will be performed by means of GALES, a finite element numerical code for the
time-dependent 2D dynamics of multi-component compressible and incompressible
magma, which has been developed by some of the RU participants. Time-space-dependent
stress conditions computed at the magma-rock interface will be employed as boundary
conditions for the numerical simulations of 2D/3D rock elasto-dynamics, taking into
account rock heterogeneities (defined within the project consortium on the basis of
previous results on Mount Etna seismic tomography experiments), and real topography.
Some of the relevant system conditions (e.g., chamber size, depth, geometry, magma
composition and volatile content, etc., to be defined within the project consortium) will be
varied in parametric studies in order to ascertain their influence on the general dynamics,
the expected signals, and the capability of external triggers to destabilize the magmatic
system and create the conditions for a new eruption. The latest multi-component models
for magma parameters (e.g. viscosity, density) will be taken into account in the modelling.
A very preliminary analysis of the effect of the very shallow (< 300 m depth) ground water
circulation and of the presence of aquifers on the expected seismic signal at the surface
will be addressed.
330
1. Preparation and storage of the GIS data base.
2. Map of the most relevant on-shore and off-shore structures and of the extent of
submarine landslides.
3. Elaboration of some seismic lines across the possible off-shore prolongation of the
Mascalucia Trecastagni faults.
4. Analysis and interpretation of elaborated seismic lines.
5. Representative eruptions of different styles, magnitude and intensities will selected.
6. Selection of representative samples and detailed “ad hoc” resampling.
7. Petrologic study of products of selected recent eruptions.
8. Estimate of relevant pre-eruptive conditions within magmatic reservoirs feeding
recent eruptions.
9. Development of combined analytical methods to obtain detailed zoning profile in
minerals.
10. System definition for the simulations of magma and rock dynamics.
11. First simulations on magma/rock dynamics.
1. Elaboration of some seismic lines across the possible off-shore prolongation of the
Pernicana fault.
2. Analysis and interpretation of elaborated seismic lines.
3. Correlation of observed structures with other seismic surveys.
4. Petrologic study of products of relevant historical eruptions.
5. Interpretation of zoning profile in minerals.
6. Reconstruction of the crystallization history within the magma chamber.
7. Additional simulations on magma/rock dynamics.
8. Simulations of magma/rock dynamics with external triggers, and definition of the
expected geophysical signals.
9. Storage of the results into the GIS data-base.
First year
Finanziato dal
Dipartimento
b
Finanziato
dall'Organismo
c = a-b
3000
0,00
9000
0,00
23000
0,00
Categoria di spesa
Importo
previsto
a
0,00
5500
0,00
331
4500
0,00
0,00
45000
0,00
Importo
previsto
a
Finanziato dal
Dipartimento
b
Finanziato
dall'Organismo
c = a-b
3000
0,00
8000
0,00
20000
0,00
Totale
Second year
Categoria di spesa
0,00
5000
0,00
4000
0,00
0,00
40000
0,00
Importo
previsto
a
Finanziato dal
Dipartimento
b
Finanziato
dall'Organismo
c = a-b
6000
0,00
17000
0,00
43000
0,00
Totale
Total
Categoria di spesa
0,00
10500
0,00
8500
0,00
Totale
85000
0,00
Name: Francesco Mazzarini, Date of birth: 23 January 1959, Nationality: Italian. 1988:
Degree in Geology, University of Pisa, Italy. 1988-1995 contract researcher for the
University of Siena in the frame of the Italian National Project of Antarctic Research
(PNRA). 1989-1994 scientific collaboration with Istituto CNUCE CNR of Pisa on Remote
Sensing and GIS application to Geology and Environment. 1991-1992 years professional
332
geologist in quarry exploitation. 1996-2001 contract researcher at the Italian National
Research Council (CNR) in Pisa. 2001-2005 fully employed as researcher at the CNR in
Pisa. 2005 employed as senior researcher (geologist) at the Istituto Nazionale di Geofisica
e Vulcanologia (INGV) in Pisa. 1996-1999 coordinator of the research unit TLR02 in the
project ‘Rilievi spettroradiometrici di superfici naturali in Antartide per uno studio
integrato con dati telerilevati’ of the PNRA. 2000-2002 coordinator of the project ‘Il
magmatismo Cenozoico del Mediterraneo centrale ed orientale: petrogenesi e significato
geodinamico’ of the CNR in Pisa. 2001-2003 coordinator of the project “Sviluppo ed
applicazione di tecniche di telerilevamento per il monitoraggio dei vulcani attivi italiani” ,
activity 5.3, granted by the Italian Civil Protection GNV-Protezione Civile. 2002-2005
coordinator of a research contract between CNR of Pisa and the municipalities of Scansano
and Magliano in T. and the AATO 6 authority for hydrogeologic, structural and
geophysical surveys in southern Tuscany. 2002-2005 coordinator of the of the geological
mapping of the Foglio 318-Follonica at the scale 1:50000 in the frame of the contract
between CNR and Tuscan region administration. 2005-Present Associate Editor of the
journal of the Geological Society of America (GSA) GEOSPHERE, ISSN: 1553-040X.
Corsaro, R. A., M. Pompilio, 2004. Buoyancy-controlled eruption of magmas at Mt Etna.
Terra Nova, 16, 16-22.
Corsaro, R. A., L. Miraglia, M. Pompilio. 2007. Petrologic evidence of a complex
plumbing system feeding the July-August 2001 eruption of Mt. Etna, Sicily, Italy,
Bulletin of Volcanology, 10.1007/s00445-006-0083-4.
Longo, A., M. Vassalli, P. Papale , M. Barsanti, 2006. Numerical simulation of convection
and mixing in magma chambers replenished with CO2-rich magma. Geophysical
Research Letters, Vol. 33, doi: 10.1029/2006GL027760.
Longo, A., D. Barbato, P. Papale, G. Saccorotti, M. Barsanti, 2008. Numerical simulation
of the dynamics of fluid oscillations in a gravitationally unstable, compositionally
stratified fissure. Special volume of the Geological London Society (in publication).
Pareschi M.T., E. Boschi, F. Mazzarini, M. Favalli, 2006. Large submarine landslides
offshore Mt. Etna. Geophysical Research Letters, Vol. 33, L13302,
doi:10.1029/2006GL026064, 2006.
333
Project V4 - FLANK
RU V4/10
Scientific Responsible: Giuseppe Nunnari, Full Professor, Dipartimento di Ingegneria
Elettrica, Elettronica e dei Sistemi, Università degli Studi di Catania, email:
RU Composition:
Man/Months 1st
phase
3
Scientific Resp.
Position
Institution
Giuseppe Nunnari
Full Professor
University of
Catania
Participants
Position
Institution
Stefano Gresta
Alessandro Spata
Placido Montalto
Flavio Cannavò
Thomas R. Walter
Full Professor
PHD student
Technician
Technologist
Researcher
University of Catania
University of Catania
INGV - Catania
INGV - Catania
GeoForschungsZentrum
(GFZ) Potsdam (D)
Man/Months 1st
phase
2
4
0
0
1
Man/Months 2nd
phase
3
Man/Months 2nd
phase
2
4
0
0
1
Task 3
WP-3A) Long term (last 300-400 years from catalogue data)
Many areas of physics take a deterministic approach: given some known values, an
outcome can be predicted accurately. Newtonian mechanics, electro-magnetism and early
optics all had this approach. However not everything in this universe is able to be analyzed
this way. Some events are apparently not dictated by any quantities (or, at least, none we
know of yet). The concept of Self-organized criticality (SOC) is an example of the latter
approach.
Self-organized criticality (SOC) is hypothesized to link the multitude of complex
phenomena observed in nature. It is a theory of the internal interactions of large nonlinear
systems. In particular, it states that large interactive systems will self-organize into a
critical state without any tuning of the parameters.
A complex system candidate to exhibit SOC behavior is characterized by the
following properties: many degrees of freedom or ways in which the system has the ability
to evolve, a continuous slow input of energy, and the presence of local thresholds store
energy, fast transport and dissipation. All these features are reasonably attributable to an
active volcano and, all the more reason, to a particular feature of the activity of a volcano,
as its flank dynamics. For this reason in this task we propose to analyze the volcanic
activity of Mt. Etna and the main effects of its flank dynamics (as eruptions and
seismicity) in terms of the self-organized criticality theory.
Since the SOC dynamics take place at the “edge of chaos” they are very sensitive to the
initial conditions. Thus resulting dynamics starting from close initial conditions diverge
exponentially in time showing different behaviors. For this reason a deterministic approach
is not able to investigate and explore the complexity governing these dynamics. Moreover,
SOC dynamics are characterized by the absence of a characteristic scale both in time and
space. The immediate consequence of this fact is that it is impossible to predict the size
334
and the time of events occurring. In this task we will investigate historical volcanological
data to investigate the conjectured SOC nature of the flank dynamic. Furthermore we will
investigate the compatibility of the volcanic flank dynamics with the assumption of SOC
behaviour of the volcanic system.
Dynamics of volcanic areas are the result of complex interaction among regional
tectonics and local magmatic forces. Information about this mechanism is contained in
geophysical and geochemical signals recorded by continuous monitoring networks.
Unfortunately information due to interesting geophysical and geochemical processes is
hidden by several noise sources and the search for recognizing volcanic effects is a very
complicated task. We believe that modern data mining techniques can help in this view.
Data mining or knowledge discovery is the nontrivial extraction of implicit, previously
unknown, and potentially useful information from large collection of data.
It can be viewed as a multidisciplinary activity because it exploits several research
disciplines of artificial intelligence such as machine learning, pattern recognition, expert
systems, and knowledge acquisition. Adding the time dimension to a database produces a
Time Series Database and introduces new aspects and challenges to the tasks of data
mining and knowledge discovery. These new aspects include a new approach to efficient
representation of time series, multivariate time series similarity and classification
algorithms.
There are many data mining tasks such as clustering, classification, regression,
content retrieval and visualization. Each task can be thought as a particular kind of
problem to be solved by a particular class of algorithms. One of the most important data
mining tasks regards the classification problem. Classification can be used both to
understand the existing pattern in data and to predict how new instances will behave.
In this task we will apply new signal processing techniques for a better
characterization of seismic and geodetic signals, and classification algorithms to
characterize patterns in multivariate time series. In particular, we plan to apply wavelet and
cross-wavelet approaches for examining relationship in time-frequency domain between
heterogeneous time series. Indeed literature results agree to state that these techniques
exhibit some advantages over traditional Fourier methods allowing a better time-frequency
resolution. Moreover, the multi-resolution property of wavelets can be incorporated into
filtering, cross-analysis and classification procedures. Proposed approaches provide a large
variety of applications from signal characterization to pattern recognition.
The target of this task is the development of software tools that implements data mining
techniques in multivariate time series database in order to recognize pre-eruptive patterns
and trends, by considering data provided by seismic and continuous GPS networks,
because these data sets seems more promising on the base of similar applications on
Stromboli (Patané et al., 2007).
Task 4
WP-4B) Numerical Models
It is common to observe that the slopes of the greatest volcanoes of the world are
usually characterized by a strong instability caused by the continuing eruptive activity, the
gravitational loading of their edifice and the activity of important regional lineaments.
The deformation and geological data on Mount Etna volcano have confirmed the
presence of a clear downward movement of its eastern flank. Instead the seismic activity of
this area have showed a complex and heterogenic stress field orientation, probably due to
335
the coexistence of a regional stress field and a local stress field produced during the several
intrusive episodes.
The aim of this research task is to establish the relations between magmatic and
tectonic structures and define the relationships between pre-eruptive, eruptive dynamics
and superficial stress fields in terms of Coulomb stress by numerical simulations.
In these last years many studies have dealt with interactions between volcanic
episodes and seismic activity in terms of static stress changes by using of Coulomb
software (Stein and King, 1994) based on analytic solution of displacements, strains and
stresses. By applying to the boundary element method it is possible to resolve many
limitations of the analytic method such as the assumption of an elastic, homogenous and
continuous half-space medium. Moreover we will be able to evaluate the topographic
effects of the displacements, strain and stresses calculations produced by a sliding surface
on the volcano. In our Coulomb stress calculations, the remote stress effects will be also
taken in account to better understand the role of the regional stress field acting on the Etna
area.
Finally, by Poly 3D software we could model complex geometry planes and the well known creeping behaviour of some structures lying on eastern flank. We propose to
calculate Coulomb stress changes by the inversion of geophysics data for a temporal period
from 1993 to 2004 in order to understand how the intrusive episodes are able to influence
the dynamic of the eastern flank on the Mount Etna volcano. These modelling studies and
results could be fundamental in order to give an important contribute for the further
evaluation of the hazard and for a possible improvement of the monitoring system.
1) A database of historic seismic and volcanological data for studying SOC aspects of
volcanic processes.
2) New algorithms to process continuous GPS and seismic signals.
3) New insights about self organized critical (SOC) behaviors of volcanic areas.
4) New algorithms to compute the Coulomb stress changes in the eastern flank of Mt Etna.
1) Pattern recognition techniques to analyze multivariate time-series.
2) Algorithm for measuring time series similarities, classification and clustering.
3) BEM modeling for simulation of relationships between pre-eruptive, eruptive dynamics
and superficial stress fields.
4) Scientific reports and papers in peer review conferences and journals.
First year
Categoria di spesa
Importo
previsto
a
Finanziato dal
Dipartimento
b
336
Finanziato
dall'Organismo
c = a-b
800000,700000
3000
0,00
32000
0,00
0,00
1000
0,00
4000
0,00
40000
0,00444
Finanziato dal
Dipartimento
b
Finanziato
dall'Organismo
c = a-b
Totale
Second year
Categoria di spesa
Importo
previsto
a
0,00
3000
0,00
32000
0,00
0,00
1000
0,00
4000
0,00
40000
0,00
Finanziato dal
Dipartimento
b
Finanziato
dall'Organismo
c = a-b
Totale
Total
Categoria di spesa
Importo
previsto
a
0,0
6000
0,00
64000
0,00
0,00
2000
0,00
8000
0,00
80000
0,00
Totale
337
Giuseppe Nunnari received the “Laurea” degree in electrical engineering (cum laudae)
from the University of Catania, Catania, Italy, in 1979. He was a software engineer in
private companies until 1983 and Researcher of the Italian National Research Council
(CNR), from May 1983 to October 1992, where he carried out research concerning the
modelling and processing of geophysical data. From November 1992 he joined with the
University of Catania, Faculty of Engineering, were he has served as associate professor of
System Theory and Automatic Control, till September 2001 and as a professor up to the
present days. His research interests include the modelling and control of dynamic systems,
signal and image processing, soft computing and modelling of environmental systems. He
is author or co-author of about 230 scientific papers published in international journals,
conference proceedings and books chapters. He has also co-authored 3 scientific books
published by international publishers. He has been involved, also as the coordinator, in
several research activities at international and national level, the most recent being the
following: Research on Active Volcanoes, Precursors, Scenarios, Hazard and Risk
(subproject V_3_6 Etna), Funded by the Italian INGV-DPC (INGV is the Italian Institute
of Geophysics and Volcanology, DPC is the Italian Department of Civil Protection), years
2004-2006, Monitoring Research Activity at Stromboli and Panarea, Funded by the Italian
INGV-DPC, years 2004-2006, Air Pollution Episodes: modelling Tools for Improved
Smog management (APPETISE) Funded by the European Union under the FP5
Framework Program, Contract IST-1999-11764, years: 2000-2002, Innovative
Methodologies for Processing SAR Interferograms, Funded by the Italian INGV, years:
2002-2004, Innovative methodologies for the integrated inversion of gravimetric and
magnetic data recorded in volcanic area (EPOT), Funded by the Italian INGV, years:20022004, Technique and method innovation in geophysical research, monitoring and early
warning at active volcanoes (TECVOLC), Funded by the European Union under the FP4
Framework Program.
G. Nunnari, G. Puglisi, F. Guglielmino (2005), Inversion of SAR data in active volcanic
areas by optimisation techniques, Non Linear Processes in Geophysics, 12: pp 863-870.
Currenti G., Del Negro C., Nunnari G., Inverse Modelling of Volcanomagnetic fields using
a genetic algorithm techniques, Geophysical International Journal, 163, pp 403-418,
2005.
Nunnari G., Bertucco L., Ferrucci F., A Neural Approach to the Integrated Inversion of
Geophisical Data Types, IEEE Transaction on Geosciences and Remote Sensing, Vol.
39, N. 4, pp 736-748, April 2001.
G. Nunnari., Modelling air pollution time-series by using wavelet functions and genetic
algorithms, (2004), Soft Computing, Springer Verlag, Vol. 8, N° 3, pp. 173-178.
G. Nunnari, An Improved Back Propagation Algorithm to Predict Episodes of Poor Air
Quality, Soft Computing, Springer Verlag, N° 10, pp. 132-139, 2006.
.
338
Project V4 - FLANK
RU V4/11
Scientific Responsible: Giuseppe Puglisi, Senior Researcher, Istituto Nazionale di
Geofisica e Vulcanologia-Sezione di Catania, Piazza Roma 2, 95123 Catania, email:
RU Composition:
Scientific Resp.
Position
Institution
Puglisi Giuseppe
Director of Research
INGV-CT
Participants
Position
Institution
Danilo Reitano (1)
Marcello Dagostino (1)
Orazio Torrisi (1)
Fabrizio Pistagna (1)
Technologist
CTER
CTER
Fellow
Antonino Drago (1)
Fellow
Silvia Cariolo (1)
CoCoPro
Gaetano Russo (1)
CoCoPro
Lizzio Sebastiano (1)
CoCoPro
INGV-CT
INGV-CT
INGV-CT
COMETA
Consortium
COMETA
Consortium
COMETA
Consortium
COMETA
Consortium
COMETA
Consortium
Alessandro Bonforte (2)
Boris Behncke (2)
Salvatore Giammanco
(2)
Francesco Guglielmino
(1&2)
Marco Neri (2)
Francesco Obrizzo (2)
Researcher
Post Doc
Researcher
Man/Months 1st
phase
3
Man/Months 2nd
phase
3
Man/Months 1st
phase
1
2
2
0
Man/Months 2nd
phase
1
2
2
0
0
0
0
0
0
0
0
0
INGV-CT
INGV-CT
INGV-CT
2
0
1
2
0
1
Researcher
INGV-CT
0
0
Researcher
Senior Technologist
INGV-CT
INGV-OV
1
1
1
1
Stefano Branca (3)
Mauro Coltelli (3)
Klaus Gwinner (3)
Emanuela De Beni (3)
Danilo Cavallaro (3)
Researcher
Senior Researcher
Researcher
Researcher
PhD Student
INGV-CT
INGV-CT
DLR Berlin
INGV-CT
INGV-CT
3
1
0
0
0
3
1
0
0
0
Rosa Anna Corsaro (4)
Lucia Miraglia (4)
Lucia Messina (4)
Lucia Civetta (4)
Researcher
Technologist
Technician
Full Professor
3
0
1
1
3
0
1
1
Valeria Di Renzo (4)
Nicole Metrich (4)
Post-doc fellow
INGV-CT
INGV-CT
INGV-CT
UNI-NA &
INGV-OV
INGV-OV
CNRS (F)
2
1
2
1
Michael Burton (5)
Tommaso Caltabiano (5)
Giuseppe Salerno (5)
Senior Researcher
Senior Technologist
PhD Student
INGV-CT
INGV-CT
INGV-CT
1
1
0
1
1
0
339
Domenico Patanè (6)
Flavio Cannavò (6)
Placido Montalto (6)
Technologist
Technician
INGV-CT
INGV-CT
INGV-CT
0
0
0
0
0
0
Alessandro Bonaccorso
(7)
Ciro Del Negro (7)
Gilda Currenti (7)
Rosalba Napoli (7)
Filippo Greco (7)
Gaetana Ganci (7)
Danila Scandura (7)
Gennaro Budetta (7)
Charles Williams (7)
Giovanni Russo (7)
INGV-CT
1
1
Senior Researcher
Researcher
Researcher
Researcher
PhD student
PhD student
Professor
Professor
1
0
1
1
1
1
1
1
1
1
0
1
1
1
1
1
1
1
Antonello Piombo (7)
Michele Dragoni (7)
Marco Aloisi ( 7)
Mimmo Palano (7)
Falk Amelung (7)
Researcher
Professor
Researcher
Researcher
Professor
1
1
1
0
1
1
1
1
0
1
Warner Marzocchi
INGV-CT
INGV-CT
INGV-CT
INGV-CT
INGV-CT
INGV-CT
INGV-CT
RPI (USA)
DMIUNICT
DF-UNIBO
DF-UNIBO
INGV-CT
INGV-CT
CSIC –
Miami
(USA)
INGV-RM1
0
0
Numbers from 1 to 7 indicate the Team to witch each participant belongs
The activities of this RU will handle all Tasks of the project, involving
multidisciplinary contributions from the different participants to the RU. In order to
organize the several activities and direct them toward their fully achievement, the
participants are grouped in seven Teams, each aimed at specific activity. So the description
of each Task, will take into account the Team/s in charge of the different activity/activities.
Throughout the project the results of different Teams will be discussed and integrated; to
this aim, in some cases, internal meetings may be organized, eventually by inviting other
RUs, to share the information among the participant to the project.
Task 1
Multidisciplinary data analysis can help researchers to evaluate the correct hazard during
volcanic and/or seismic events connected to the flank dynamics. New software solutions
and available data processing can perform useful relationship between related patterns. The
goal of this activity is to design and to develop a Web-GIS base infrastructure able to
manage and disseminate different kinds of data shared among the different UR
participating to the Project, including those produced during the project. A user-friendly
web interface will be realized, able to guarantee also different access levels and data
representations. The web infrastructure, so designed, will be available to the project
members and suitable to present results outside for scientific requests. This activity will
benefit from the facilities provided from the COMETA consortium (PON 2006,
www.consorzio-cometa.it), in which the INGV participates, and in particular from the
capability to use massive calculation and very large amount of storage space. The design of
plant regarding database, storage, Web/GIS interface will profit form these facilities. Also
the modeling will be developed into the Task 4, may be verified inside the GRID
statement. This activity will be carried out in cooperation with LAVA project.
In details, this activity can be divided into five different steps:
i. Design and development of the complete database infrastructure ensuring the maximum
compatibility with the WOVOdat standards.
340
ii. Implementation of an inventory with data and metadata coming from different research
fields.
iii. Design of the necessary layers and custom software that processes data and presents
them into a GIS interface.
iv. Realization of a Storage Area Network to guarantee redundancy and robustness.
v. Tests
This activity is performed by the Team 1, leaded by D. Reitano.
Task 2
WP-2A) Surface (Integration of the main structural and kinematic features of the on-shore
portion of the “unstable” flanks).
Team 2, leaded by A. Bonforte, will review the structural, geodetic and geochemistry data
regarding several fundamental fault systems that are connected to the movements of the
flanks of the volcano. These are either tectonic structures already reported in the literature,
but only partially described in detail in scientific publications, or faults whose existence is
only suggested on the base of geodetic, seismic or satellite data. This activity will be carry
out through the following phases:
- Available GPS and DInSAR data will be analyzed in order to identify discontinuities in
the ground deformation fields imputable to the activity of the faults dissecting the eastern
flank of the volcano; this will allow to reconstruct the geometry, kinematics and dynamics
of these faults.
- Structural analysis and mapping of the fault systems, selected also considering the
previous phase. Field surveys will be aimed at understanding its kinematics, rates of
movement, and possibile fracturing during aseismic creep, wherever present.
- Maps and/or profiles of distribution of anomalous soil gas emissions (CO2 efflux, 222Rn
and 220Rn activities, and possibly He concentrations) related to outcropping or buried
faults. This analysis will serve to support the field surveys mentioned in the previous point.
WP-2A) Surface (Integration of different data sets to identify the main structural features
of the off-shore portion of the “unstable” flanks and relationships with the on-shore
coastal portion).
New detailed geological and structural investigations of Etna performed for the
realization of the new geological map (Branca et al. 2008) allow to define an update
tectonic setting of the volcano. The main structural lineaments of Etna were extracted by
different data sources integration of: a) geological field mapping; b) analysis of high
resolution DTM; c) historical ground surface rupture mapping (Azzaro et al. 2008). This
data set will be analyzed in order to constrain the age and the kinematics of the tectonic
lineaments for understand their complex relationship. Afterward the analysis will be aimed
at linking the main tectonic structures of Etna eastern flank with the morpho-lineaments
recognized in the Ionian off-shore on the shallow- and deep-water bathymetric maps. The
integrated analyses between on- and off-shore structures should improve the knowledge of
the dynamics of the unstable eastern flank of the volcano. This activity is performed from
Team 3, leaded by S. Branca, in cooperation with RU-05.
Task 3
WP-3A) Long term (last 300-400 years from catalogue data; Analysis of the historical
volcanic events to define the main eruptions probably related to the flank dynamics)
About 3 ka of Etna activity is documented in the historical sources, giving the
volcanologists a unique and very long record for an active volcano, though only after the
341
second half of 17th century this record of both central and flank eruptions is complete and
accurate (Branca and Del Carlo, 2004). Starting from the detailed data-set of the eruptive
record realized by Branca and Del Carlo (2004 and 2005) a new analyses from the second
half of 17th century of the original sources must be done in order to study the relationship
between the intrusive processes of the flank eruptions and the dynamics of the eastern
flank structures. Furthermore, we will investigate the relationship between the central and
flank activity in order to identify the possible presence of systematic trends in eruptive
activity and define the short-term behavior of the volcano. Concerning the flank eruption
the re-examination of the historical source must be focused on the reconstruction of the
surface eruptive processes that have accompanied the magma intrusion. This
methodological approach will be compare with the analysis of the historical seismicity
with the aim of define the occurrence of eruptive events that are strictly related to the
activation of the main seismogenic faults of the Etna flanks, as the case of the 2002-03
eruption. This activity is performed from Team 3, leaded by S. Branca, in cooperation with
RU-04 and RU-10.
In this Work Package several activities will be carried out by different Teams, with
different aims.
Assessment of a complete volcanological data-set
The Team 4 (leaded by R.A. Corsaro) will perform a specific activity to investigate the
relationship among eruptive activity, magmatic process of Mt. Etna shallow plumbing
system and the dynamics volcano eastern flank, throughout the period 1993-2004. To this
purpose, the first year will be aimed at acquiring a complete data set of petrologic data
(petrography, mineral and glass chemistry, major and trace elements composition, Sr-Nd
isotopes, olivine-hosted melt inclusions) on volcanics erupted from 1993 to 2004. These
samples were collected during monitoring activities at INGV-CT, and will be selected on
the base of critical review of current literature. In particular the activity of the Summit
Craters will be focused because a detailed data-set of 2001, 2002-03 and 2004-05 flank
eruptions are already available.
Analysis of each data-set
Teams 2, 4, 5, 6 and 7 (leaded by A. Bonforte, R.A. Corsaro, M. Burton, M. Mattia, G.
Puglisi and A. Bonaccorso, respectively) will perform a temporal and/or spatial analysis of
each data set, owing their expertise on different monitoring disciplines. This activity will
be aimed at characterizing the relationships between each type of data and flank dynamics.
Time series provided from permanent stations (e.g. GPS, seismic, gravity or magnetic
stations) or repeated surveys (e.g. SO2 flux measurements, GPS campaigns) will be
analyzed. Petrologic data will be analyzed to reconstruct the temporal evolution of
magmatic processes occurring in Mt. Etna plumbing system.
Multidisciplinary analysis of the different data-sets.
Teams 2 and 4 (leaded by A. Bonforte and R.A. Corsaro) will carry out a review and the
re-interpretation of eruptive and deformative events during the period 1993-2004, together
with their possible role in the framework of flank instability. This approach will be
strongly multidisciplinary, aimed at categorizing volcanological, petrological, structural,
geodetic, satellite and geochemical data. The ground deformation measured on the eastern
flank of Mt. Etna from 1993 to 2004 will be deeply reviewed and correlated to the eruptive
activity, in order to understand their role in the framework of flank instability; this activity
342
will pay particular attention to the period of the 2001, 2002-2003 and 2004-2005 flank
eruptions. These data will thus allow a comparison between the different data sets, aided
by the construction of space-time diagrams useful to identify anomalies potentially induced
and/or correlated with flank movements and volcanism.
The analysis of time sequences of soil gas data from selected high-degassing sites on the
volcano’s flanks will be carried out, to highlight changes in gas rates/concentrations related
to changes in large-scale ground permeability and/or to shallow magma intrusions.
Finally the comparison of time-related sequences of petrologic data with other temporally
constrained data-sets concerning geology (e.g. eruptive fracture distribution/evolution),
geophysics (e.g. seismicity, ground deformation or gravimetry) and geochemistry of gases
from soils or plumes, should allow inferring the possible relationship between magmatic
processes of Mt. Etna shallow plumbing system and the dynamics of the volcano eastern
flank during the considered period.
Multivariate statistical analysis of the different data-sets
Seismic and deformation monitoring approaches have already proven to be the most
reliable and diagnostic in early detection and tracking of volcanic unrest. In recent years,
automated analysis techniques to uncover previously undetected relationships among data
items – usually defined as “data mining” techniques - have become a powerful method to
extract a base of knowledge from large amounts of data by correlating and modelling
heterogeneous data.
Recently, a joint analysis between seismic and high frequency GPS signals (1 Hz) has led
to observe significant changes before the main events of the 2007 eruption at Stromboli
(Patanè et al, 2007). The problem that arises for an immediate use of this innovative
technique is essentially to characterize the geophysical signals with respect to the
perturbation sources (e.g. meteorological conditions). In this project similar techniques will
be developed to study the dynamics of Mt Etna through signals acquired by permanent
networks, focusing in particular those information relevant to the flank dynamic, e.g. by
analyzing the deformations or seismic signals acquired at stations located in the eastern
flank.
We plan to undertake joint correlation analysis of these multivariate datasets. Our purposes
are the development of both a time series database, by using data acquired from permanent
installations, and a suite of software, witch implements data mining and knowledge
discovery algorithms able to increase our knowledge of the dynamics and the interaction of
different geophysical processes. In this task we apply new signal processing technique for
a better characterization of seismic and geodetic signals, and in particular a wavelet and
cross-wavelet approach is proposed.
In the frequency domain, the using of Wavelet helps to improve significantly the signal
analysis, overcoming the limitations of the Fourier transform (FFT and STFT) to get all
possible information about the temporal localization of a band of frequencies that
otherwise could be lost in the analytical process. In particular, they have advantages over
traditional Fourier methods in analyzing physical situations where the signal contains
discontinuities, sharp spikes or it is affected by a great noise. Moreover wavelet coherence
analysis allows to manage and compare heterogeneous data.
During the project the possibility to introduce in the data mining other datasets will be
taken into account, even by considering other approaches than wavelet, in order to
improve the capability of applying it in a multidisciplinary monitoring system as the
existing one on Mt. Etna is.
Finally, the target of this task is the realization of a prototype system that uses knowledge
discovered from acquired data in order to discover patterns clearly related to the interaction
between flank dynamic and volcanic activity.
343
This activity is performed from Team 6, led by G. Puglisi, in cooperation with RU-10.
Task 4
WP- 4A) Definition of parameters
The 2002-03 eruption represents the first time that a time-dependent deformation has been
observed at Mt. Etna. In order to evaluate which mechanism is involved into the posteruptive deformation process, two time-dependent relaxation models may be used to
interpret the GPS data collected both at permanent and non-permanent stations. Each
model allows evaluating some parameters of the shallow crusts involved in the
deformation event (e.g. viscosity, elastic shear modulus, layers-thickness, etc.) by
considering the geologic and seismic information available for the investigated area. These
parameters could be take into account for future numeric modeling in order to better
understand the ground deformation pattern connected to the flank dynamics of Etna.
Team 7, leaded by A. Bonaccorso, will apply Finite Element modeling to interpret the
ground deformations and to infer on the static stress distribution related to the flank
dynamics.
Geodetic data inversion (SAR, GPS, leveling, EDM) using Finite Element Method –
Dislocation source inversions performed using different kind of static deformation data,
such as GPS displacements, SAR imagery, leveling and EDM measurements, suggest that
slip along a fault is usually not uniform and is better modeled as a distribution of
dislocation sources. To this aim, an automatic procedure for geodetic data inversion will be
developed to estimate slip distribution along the fault interfaces. 3D finite element models
(FEMs) will be implemented to compute synthetic Green’s functions for static
displacement. FEM-generated synthetic Green’s functions will be combined with inverse
methods to obtain the dislocation distributions that explain the observed ground
deformation. Tests on displacement sensitivities to material property distributions will be
also performed. To speed up the computation time, the procedure will be parallelized to
run on cluster.
Volcano-tectonic interaction by means of static stress changes - Coulomb stress changes
computations will be carried out to investigate the complex interaction between magmatic
intrusions and tectonic processes responsible for the kinematics of the seismogenic
structures at Etna volcano. The dynamics of volcanic processes usually involve high strain
and stress changes, which induce strong perturbations in the local stress regime. We
propose: (i) 3D numerical computations of static stress changes to include both the
irregular geometric and the complex tectonic structures for which analytical models are no
longer applicable; (ii) statistical correlation analysis between positive Coulomb stress
changes areas and earthquake locations. The estimate of the variations in the Coulomb
stress together with a statistical analysis of the intercurrence times of seismic and volcanic
crises at Etna could supply a quantitative esteem of the reactivation of seismogenetic
structures.
Thermo-Mechanical modeling – A coupled thermo-mechanical model will be implemented
to evaluate time-dependent changes in long-term deformation and quasi-static stress field.
In volcanic areas, the high temperature around magmatic sources can strongly perturb the
geothermal gradient inducing variations in the rheological behavior in the nearby rocks,
making the elastic approximation inappropriate. Long-term deformation can be affected by
combination of thermoelastic and viscoelastic mechanisms. Numerical models will be
developed to investigate: (i) thermo-elastic deformation caused by thermal changes within
344
the magmatic source as a result of intrusion of new magma; (b) viscoelastic deformation
caused by viscoelastic response of the medium.
Task 5
The Team led by A. Bonforte will consider three aspects of the volcanological and
geological hazard related to the flank dynamics: fissure/fracture system distributions,
aseismic creep and landslides.
The role of tectonic structures related to flank displacement in the triggering or facilitating
of effusive and/or explosive eruptive activity will be evaluated in order to define the areas
of the volcano where fissures/fractures related to flank dynamics may open. To achieve
this goal, we will firstly define, in cooperation with the LAVA project, the distribution of
all fracture/fissure systems, and then we will analyze their kinematics in order to establish
their role in the flank dynamics.
The hazard posed by structures capable to produce aseismic creep will be evaluated. Many
faults involved in the flank movements at Etna do actually move virtually continuously (at
average rates around ~1-2 cm/yr), fracturing the ground, but without producing any
significant seismicity. Such phenomena occur on several parts of the eastern and
southeaster flanks, affecting the stability of numerous man-made structures of varying
importance. This activity will be aimed at quantifying the creep affecting the principal lifelines (e.g. the Catania-Messina highway or the railway).
In some cases, the movement of the faults involved in the movements of the unstable
flanks intersects sub-vertical topographic surfaces, facilitating or triggering, with their
movement, phenomena of gravitational instability (such as the Vena-Presa landslide). In
these cases the role of these tectonic structures in the triggering or facilitating of superficial
gravitational movements will be evaluated.
Prototypal procedures to be used by the Operations Centre of DPC in case of unrest
along the unstable flanks, highlighting possible hazard as a function of the boundary
conditions.
Finally, a few participants to this RU are shared with LAVA project to perform a
preliminary valuation, in cooperative mode with LAVA project, about the possibility to
apply the BET (Bayesian Event Tree) approach for attempting to assess a probabilistic
hazard evaluation of either opening new fissure systems, induced from flank dynamics, or
increasing the stress field on the flank due to new magma intrusions.
1. Database structure, study of different WEB/GIS systems; Site realization; Database
integration.
2. Structural analysis derived from the integration of surface surveys, geodetic data
and soil gas surveys.
3. Definition of the main tectonic features related to flank slip.
4. Preliminary definition of the main eruptive events and their volcanological features
related to the flank dynamic.
5. Petrologic data set (petrography, mineral and glass chemistry, major and trace
elements composition, Sr-Nd isotopes, olivine-hosted melt inclusions) of selected
volcanics from Summit Craters relevant to 1993-2004.
6. Results of the review and the re-interpretation of eruptive and deformative events
during the period 1993-2004 (preliminary evaluations).
345
7. Inversion of time-dependent relaxation models by using GPS data time series.
8. Developing and testing the FEM geodetic inversion procedure.
9. Numerical code for evaluating the viscoelastic deformation.
10. Preliminary results of the parameterization of creep and landslide areas for
volcano-structural hazard evaluations.
11. Map of distribution of the fracture and eruptive fissure systems
1. Data representations, web interfaces, GIS; Final documentations; manuals.
2. Correlation between on- and off-shore tectonic structures and their relationship to
the eastern flank dynamic.
3. Recognition of the eruptive processes of the past 3-4 centuries related to the
activation of the main seismogenic faults.
4. Time-related petrologic sequence correlated with other temporally constrained
data-set concerning geology, geophysics and geochemistry of gases.
5. Results of the review and the re-interpretation of eruptive and deformative events
during the period 1993-2004 (detailed results of specific volcanic events).
6. Evaluation of elastic and geometrical parameters (e.g. viscosity, elastic shear
modulus, layers-thickness, etc.) of the Pernicana area and comparison with
available geological and geophysical information.
7. Coulomb stress change maps on seismogenic structures.
8. Numerical code for evaluating the thermoelastic deformation.
9. FEM geodetic data inversion code.
10. Analysis of the dynamics of the principal structural trends involved in the volcano
flank dynamics. Integration of all the collected data and final volcano-structural
hazard evaluations.
11. Prototypal procedures to be used by the Operations Centre of DPC in case of unrest
along the unstable flanks, highlighting possible hazard as a function of the
boundary conditions.
First year
Finanziato dal
Dipartimento
b
Finanziato
dall'Organismo
c = a-b
3100
0,00
12000
0,00
13000
0,00
6000
0,00
10000
0,00
4900
0,00
Totale
49000
0,00
Categoria di spesa
346
Importo
previsto
a
Second year
Finanziato dal
Dipartimento
b
Finanziato
dall'Organismo
c = a-b
2900
0,00
8000
0,00
11000
0,00
Categoria di spesa
Importo
previsto
a
0,00
15000
0,00
4100
0,00
Totale
41000
0,00
Finanziato dal
Dipartimento
b
Finanziato
dall'Organismo
c = a-b
6000
0,00
20000
0,00
24000
0,00
6000
0,00
25000
0,00
9000
0,00
Totale
90000
0,00
Total
Categoria di spesa
Importo
previsto
a
Giuseppe Puglisi born in Catania (Italy) on 6th May 1958. Since 1988 Giuseppe Puglisi has
been Researcher with the CNR-IIV, now the “Sezione di Catania” of INGV. He is senior
scientist at INGV-CT since 2002.
His research activity concerns the dynamic of the volcanoes and surrounding seismogenic
areas investigated by using geodetic techniques, mainly GPS and SAR interferometry. He
also deals, with researches relevant to the ground deformation data inversion problems,
mainly using numerical optimization techniques. In the frame of these research activities
347
he was involved as Contractor or PI on international (ESA, EC) and national (ASI or GNV,
INGV) research projects.
Since 2002 he is responsible of the INGV–CT branch that manages the geodetic
monitoring networks on the Sicilian volcanoes and seismic areas. Since 2004 he is also
coordinator of the INGV geodetic monitoring surveillance activities on the Italian
volcanoes. During the 2002-‘03 and 2007 eruptions of Stromboli volcano he was
responsible of the ground deformations monitoring systems. He is authors or co-authors of
more than fifty papers published in international and national scientific journals as well as
in specialized books, most of them devoted to study of the effects of flank dynamics on
volcanoes, as Mt. Etna and Stromboli.
Bonaccorso, A., Bonforte A., Guglielmino F., Palano M. and Puglisi G. (2006), Composite
ground deformation pattern forerunning the 2004–2005 Mount Etna eruption, J.
Geophys. Res.,111, B12, doi:10.1029/2005JB004206.
Currenti, G., Del Negro, C., Ganci, G. (2007). Modelling of ground deformation and
gravity fields using finite element method: an application to Etna volcano. Geophys. J.
Int., doi: 10.1111/j.1365-246X.2007.03380.x.
Bonforte, A. and Puglisi G. (2006), Dynamics of the eastern flank of Mt. Etna volcano
(Italy) investigated by a dense GPS network, J. Volcanol. Geoth. Res., 153, 3-4, 357-369.
Branca S., Del Carlo P. (2005). Types of eruptions of Etna Volcano AD 1670-2003:
Implications for short-term eruptive behaviour. Bull. Volcanol., 67, 732-742.
Neri M., Guglielmino F. and Rust D. (2007), Flank instability on Mount Etna: radon, radar
interferometry and geodetic data from the southern boundary of the unstable sector. J.
Geophys. Res., 112, doi:10.1029/2006JB004756.
348
Project V4 - FLANK
RU V4/12
Scientific Responsible: Agata Siniscalchi, Associate Professor, Università di Bari
(UNIBA), Dipartimento di Geologia e Geofisica, Campus Universitario, Via Orabona 4,
70125 Bari, email: [email protected], tel: 080-5442376, fax: 080 5442625
RU Composition:
Scientific Resp.
Position
Institution
Agata Siniscalchi
Professore
Associato
UNIBA
Man/Months 1st
phase
3
Man/Months 2nd
phase
3
Man/Months 2nd
phase
2
Participants
Position
Institution
Mariano Loddo
Professore
Ordinario
Professore
Ordinario
Tecnico
Dottorando
Assegnista
Professore
Associato
Ricercatore
Dottorando
UNIBA
Man/Months 1st
phase
2
UNIBA
2
2
UNIBA
UNIBA
UNIBA
UNIBA
2
3
2
1
2
3
1
1
IMAA-CNR-PZ
IMAA-CNR-PZ
2
2
2
2
Domenico
Schiavone
Cosimo Magrì
Pierpaolo Moretti
Ida Diaferia
Marcello De Giosa
Marianna Balasco
Gerardo Romano
Task 2
WP-2B) Depth
In the framework of the project INGV-DPC 2005-2007 electrical resistivity tomography
(ERT) and magnetotelluric (MT) techniques were applied along three profiles crossing the
Pernicana fault system (PFS) on the Eastern Etnean flank. By the inversion of such data
detailed resistivity model were obtained, which well define three resistivity main layers:
1) a shallow resistive layer (thousands ohm.m) related to the volcanic cover, reaching its
major thickness towards the south in each section and decreasing from west to east.
2) a conductive intermediate layer related to volcanic sedimentary substratum, with higher
conductivity values in correspondence of the fault. Its thickness is greater in the unstable
sector and major thickness are assumed towards the south.
3) a resistive bedrock.
The recovered depth of the horizon between the conductive zone and the resistive bedrock
surprisingly matches with the location of earthquake hypocenters recovered by
seismological studies. This horizon is characterized even by an abrupt change of the
geoelectrical strikes from about 5° to 35°-40°. By such results we retain that it probably
represents the basal decollement of the mobile sector within the PFS.
On the basis of these results, these techniques can be retained suitable to contribute to the
volume evaluation of the mobile sector. In particular we organize the UR activity both:
- on the acquisition of electromagnetic data in unexplored areas of the flank, and
349
- in the application of a recent statistical approach for the interpretation of the
resistivity models in order to control the association between the electrical layers and the
lithological units characterizing the flank. This process is considered a significant
improvement in order to carefully define the geometrical parameters for the numerical
models developed by Task 4.
In the present research project new magnetotelluric soundings will be performed in
the Northern part of the Eastern Etnean flank in order to further constrain the nature and
depth of the inferred basal decollement (Pernicana fault). Therefore, an areal MT
investigation is planned along the westernmost part of the Pernicana Fault; in the same area
a self-potential (SP) survey will be performed. These two activities are focused to evaluate,
in addition to the depth of the decollement, the relationship between the hydrothermal
system related to the volcano and the structures characterizing the PFS and to contribute to
a better definition of the structural and lithostratigraphic arrangement of the Rift area.
In the Southern portion of the flank we planned a MT profile (Mascalcia-Acireale)
perpendicular to the faults and to the coast; three ERT segments will be performed along
the same profile to ensure higher resolution in the shallower part of the investigated
section, especially across the main discontinuities, in order to define the relationships
among different structures. All the MT acquisition will be remote referenced to permit
noise reduction in the urbanized areas where longer acquisition time will be ensured. The
exploration depth of this survey is scheduled to be at least 8-10 km.
The dimensionality and directionality analysis of the MT transfer function will be
supported even by the analysis of the magnetic transfer function, in order to recognize
eventual electrical anisotropic effects.
An accurate evaluation of the resistivity models will be performed via the joint
interpretation with other independent geophysical models (e.g. density, velocity) available
in the same areas. This stage will be quantitatively approached by statistical methods of
correlation among multiple physical properties. During the first year, this strategy will be
applied on the resistivity models obtained in the previous project.
1. ERT profiles (acquisition and modeling) on the southern block.
2. MT and SP data acquisition in the North.
3. Integrated interpretation of the previous resistivity model with velocity and density
models.
4. MT data acquisition along the Mascalucia-Acireale profile (30%).
1.
2.
3.
4.
5.
350
Finishing MT data acquisition along the Mascalucia-Acireale profile.
Map of distribution of the geoelectrical strikes at different estimated depth.
SP map and Resistivity model (2D o 3D) for the areal survey in NE Rift area.
Resistivity model across the MT profile Mascalucia-Acireale.
Integrated interpretation of the profile Mascalucia-Acireale.
First year
Finanziato dal
Dipartimento
b
Finanziato
dall'Organismo
c = a-b
4000
800000,700000
8000
0,00
20000
0,00
Categoria di spesa
Importo
previsto
a
0,00
4000
0,00
4000
0,00
446000,00
40000
0,00444
Importo
previsto
a
Finanziato dal
Dipartimento
b
Finanziato
dall'Organismo
c = a-b
2500
0,00
5000
0,00
14000
0,00
Totale
Second year
Categoria di spesa
0,00
1000
0,00
2500
0,00
0,00
25000
0,00
Importo
previsto
a
Finanziato dal
Dipartimento
b
Finanziato
dall'Organismo
c = a-b
6500
0,0
13000
0,00
Totale
Total
Categoria di spesa
351
34000
0,00
0,00
5000
0,00
6500
0,00
65000
0,00
Totale
0,00
Agata Siniscalchi received the degree in physics (University of Naples) in 1984 and PhD
(Geophysics and Volcanology) in 1989. She made research and continuing education on
electromagnetic methods at the Institut für Geophysik und Metereologie of the University
of Münster (Germany) and at the Macquarie University in Sidney (Australia). From 1989
to 1998 she was researcher at the GeomareSud Institute (CNR, Naples), where she was
member of the Scientific Committee.
From 1998 she is Associate Professor in Applied Geophysics at the University of Bari, II
Faculty of Science.
In the framework of applied geophysics, her research activity is mainly devoted to the
methodological and applicative problems of the electromagnetic methods, expecially
magnetotellurics. The main methodological results were the definition of two new
electromagnetic prospecting techniques, studies on the electrical dispersion effects in
magnetotellurics and signal data processing. The experimental research, involving
magnetotellurics integrated with other geophysical methods, interested geothermal (the
Siena Graben and Western Alps), volcanic (Phlaegrean Fields, Vesuvius and Etna) and
seismic areas (Colfiorito, Val d'Agri and Pollino fault areas) or structural studies in the
framework of the CROP 03 and CROP 04 projects.
Scientific partner of projects financied by MIUR, GNDT, INGV-DPC and ENI.
Agata Siniscalchi is author of 45 papers on international and national journals. She is
member of SEG (Society of Exploration Geophysicists) and of EAEG (European
Association of Exploration Geophysicists).
Diaferia I., M. Barchi, M. Loddo, D. Schiavone, Siniscalchi A. (2006) – Detailed imaging
of tectonic structures by multiscale Earth resistivity tomographies: The Colfiorito normal
faults (central Italy). Geophys. Res. Lett. vol. 33, ISSN: 0094-8276.
doi:10.1029/2006GL025828 L09305.
Mauriello P, Patella D, Petrillo Z, Siniscalchi A., Iuliano T. and Del Negro C. (2004) – A
geophysical study of the Mt.Etna volcanic area. In: The Mt. Etna Volcano, AGU
Geophysical Monograph Series, Ed.s S. Calvari, A. Bonaccorso, M. Coltelli, C. Del
Negro, and S. Falsaperla., AGU, pp. 273-291 , ISBN: 0-87590-408-4.
Patella D., Petrillo Z., Siniscalchi A., Improta L., Di Fiore B. (2005) – A magnetotelluric
study about the CROP-04 transect across the Southern Apennines, Italy. In “Crop-Crustal
seismic exploration of the Mediterranean region”, Ed I. Finetti, Elsevier, ISBN: 0-44450693-4.
Schiavone D., Loddo M. (2007) – 3-D density model of Mt. Etna volcano (Southern Italy).
J. Volcanology and Geothermal Research, 164, pp. 161–175, ISSN: 0377-0273.
352
Balasco M., I. Diaferia, A. Giocoli, V. Lapenna, M. Loddo, C. Magrì, S. Piscitelli, E.
Rizzo, G. Romano, A. Siniscalchi e S. Tripaldi. (2008) – Structural imaging of the
Pernicana Fault System through the joint use of electrical and magnetotelluric
investigation. Geophysical Research Abstracts, Vol. 10, EGU General Assembly 2008.
353
354

project v4 – flank - L`Istituto

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