Structural assessment of Mount Etna volcano from Permanent Scatterers analysis

A study of the deformation pattern of Mount Etna volcano based on the results from the Permanent Scatterers (PS) technique is reported. Ground motion data provided by the interferometric synthetic aperture radar (InSAR) PS technique from 1995 to 2000 are compared and validated by GPS data. An analysis of the ascending and descending line of sight (LOS) components of ground velocities has yielded detailed ground deformation maps and cross sections. This analysis allows detection and constraint of discontinuities in the surface velocity field. LOS velocities have then been combined to calculate the vertical and horizontal (E-W) ground velocities. A wide inflation of the edifice has been detected on the western and northern flanks (over an area of about 350 km2). A seaward motion of the eastern and southern flanks has also been measured. PS data allows the geometry and kinematics of the several blocks composing the unstable flanks to be defined even in the highly urbanized areas, and their displacement rates have been measured with millimeter precision. This analysis reveals the extension of some features beyond their field evidences and defines new important features. The results of this work depict a new comprehensive kinematic model of the volcano highlighting the gravitational reorganization of the unbuttressed volcanic pile on its slippery clay basement on the southern flank, but an additional drag force due to a strong subsidence of the continental margin facing the Etna volcano is necessary to explain the PS velocity field observed on the eastern flank.

[1]  Pierre Briole,et al.  Active spreading and regional extension at Mount Etna imaged by SAR interferometry , 2001 .

[2]  A. Borgia,et al.  Importance of gravitational spreading in the tectonic and volcanic evolution of Mount Etna , 1992, Nature.

[3]  Giuseppe Puglisi,et al.  Dynamics of the eastern flank of Mt. Etna volcano (Italy) investigated by a dense GPS network , 2006 .

[4]  Fabio Rocca,et al.  Permanent scatterers in SAR interferometry , 1999, Remote Sensing.

[5]  Francesco Guglielmino,et al.  Flank instability on Mount Etna: Radon, radar interferometry, and geodetic data from the southwestern boundary of the unstable sector , 2007 .

[6]  R. Azzaro,et al.  New evidence for the form and extent of the Pernicana Fault System (Mt. Etna) from structural and soil–gas surveying , 1998 .

[7]  John C. Curlander,et al.  Synthetic Aperture Radar: Systems and Signal Processing , 1991 .

[8]  J. Bousquet,et al.  The Tectonics and Geodynamics of Mt. Etna: Synthesis and Interpretation of Geological and Geophysical Data , 2013 .

[9]  Riccardo Lanari,et al.  Dynamic deformation of Etna volcano observed by satellite radar interferometry , 1998, IGARSS '98. Sensing and Managing the Environment. 1998 IEEE International Geoscience and Remote Sensing. Symposium Proceedings. (Cat. No.98CH36174).

[10]  Pierre Briole,et al.  Volcano‐wide fringes in ERS synthetic aperture radar interferograms of Etna (1992–1998): Deformation or tropospheric effect? , 2000 .

[11]  Christophe Delacourt,et al.  Post‐eruptive deformation associated with the 1986–87 and 1989 lava flows of Etna detected by radar interferometry , 1997 .

[12]  Mimmo Palano,et al.  Intrusive mechanism of the 2002 NE-rift eruption at Mt Etna (Italy) modelled using GPS and gravity data , 2007 .

[13]  A. Ferretti,et al.  Dynamics of Mount Etna before, during, and after the July-August 2001 eruption inferred from GPS and differential synthetic aperture radar interferometry data , 2008 .

[14]  Salvatore Gambino,et al.  Intrusion of eccentric dikes: The case of the 2001 eruption and its role in the dynamics of Mt. Etna volcano , 2009 .

[15]  Fabio Rocca,et al.  Monitoring landslides and tectonic motions with the Permanent Scatterers Technique , 2003 .

[16]  Kinematics and strain analyses of the eastern segment of the Pernicana Fault (Mt. Etna, Italy) derived from geodetic techniques (1997-2005) , 2006 .

[17]  Geometric and kinematic variations along the active Pernicana fault: Implication for the dynamics of Mount Etna NE flank (Italy) , 2007 .

[18]  Fabio Rocca,et al.  Nonlinear subsidence rate estimation using permanent scatterers in differential SAR interferometry , 2000, IEEE Trans. Geosci. Remote. Sens..

[19]  Howard A. Zebker,et al.  Decorrelation in interferometric radar echoes , 1992, IEEE Trans. Geosci. Remote. Sens..

[20]  Giuseppe Puglisi,et al.  Dynamics of Mount Etna Volcano inferred from static and kinematic GPS measurements , 2004 .

[21]  Howard A. Zebker,et al.  Correction for interferometric synthetic aperture radar atmospheric phase artifacts using time series of zenith wet delay observations from a GPS network , 2006 .

[22]  F. Guglielmino,et al.  Ground deformation modeling of flank dynamics prior to the 2002 eruption of Mt. Etna , 2007 .

[23]  David A. Seal,et al.  The Shuttle Radar Topography Mission , 2007 .

[24]  Mimmo Palano,et al.  Feeding system and magma storage beneath Mt. Etna as revealed by recent inflation/deflation cycles , 2008 .

[25]  Boris Behncke,et al.  The role of the Pernicana Fault System in the spreading of Mt. Etna (Italy) during the 2002–2003 eruption , 2004 .

[26]  G. Nunnari,et al.  The global positioning system as a useful technique for measuring ground deformations in volcanic areas , 1994 .

[27]  D. Massonnet,et al.  Deflation of Mount Etna monitored by spaceborne radar interferometry , 1995, Nature.

[28]  P. Rosen,et al.  Atmospheric effects in interferometric synthetic aperture radar surface deformation and topographic maps , 1997 .

[29]  D. Patanè,et al.  Faulting on the western flank of Mt Etna and magma intrusions in the shallow crust , 2007 .

[30]  M. Neri,et al.  The boundaries of large-scale collapse on the flanks of Mount Etna, Sicily , 1996, Geological Society, London, Special Publications.

[31]  Paola Del Carlo,et al.  Eruptions of Mt. Etna during the past 3,200 years: A revised compilation integrating the historical and stratigraphic records , 2004 .

[32]  Giuseppe Puglisi,et al.  Magma uprising and flank dynamics on Mount Etna volcano, studied using GPS data (1994–1995) , 2003 .

[33]  K. Feigl,et al.  Discrimination of geophysical phenomena in satellite radar interferograms , 1995 .

[34]  Mimmo Palano,et al.  A syn-eruptive ground deformation episode measured by GPS, during the 2001 eruption on the upper southern flank of Mt Etna , 2004 .

[35]  G. Puglisi,et al.  Ground deformation patterns on Mount Etna, 1992 to 1994, inferred from GPS data , 2001 .

[36]  Mimmo Palano,et al.  Composite ground deformation pattern forerunning the 2004–2005 Mount Etna eruption , 2006 .

[37]  A. Borgia,et al.  Scaled experiments of volcanic spreading , 1996 .

[38]  M. Tesauro,et al.  Actively growing anticlines beneath catania from the distal motion of Mount Etna's Decollement measured by SAR interferometry and GPS , 2000 .

[39]  George F. Jenks,et al.  ERROR ON CHOROPLETHIC MAPS: DEFINITION, MEASUREMENT, REDUCTION , 1971 .

[40]  Pierre Briole,et al.  Twelve Years of Ground Deformation Studies on Mt. Etna Volcano Based on Gps Surveys , 2004 .

[41]  Fabio Rocca,et al.  Calibration of atmospheric effects on SAR interferograms by GPS and local atmosphere models: first results , 2001 .

[42]  N. Houlié,et al.  Large scale ground deformation of Etna observed by GPS between 1994 and 2001 , 2003 .