The ground deformation of the south-eastern flank of Mount Etna monitored by GNSS and SAR interferometry from 2016 to 2019

The south-eastern sector of the Mount Etna, Italy, is characterized by numerous active faults, in particular the Belpasso–Ognina lineament, the Tremestieri–San Gregorio–Acitrezza fault, the Trecastagni fault and the Fiandaca–Nizzeti fault including the Timpe Fault System. Their activity is the result of both volcanism and tectonics. Here, we analyse the ground deformation occurred from 2016 to 2019 across those active faults by using the GNSS data acquired at 22 permanent stations and 35 campaign points observed by the Etna Observatory (INGV) and by the University of Catania. We also use the time-series of line of sight displacement of permanent scatterers SENTINEL-1 A-DInSAR obtained by using the P-SBAS tool of the ESA GEP-TEP (Geohazards Thematic Exploitation Platform) service. We discriminate the contributions of the regional tectonic strain, the inflations, the deflations of the volcano and the gravitational sliding in order to analyse the deformation along the faults of the south-eastern flank of Etna. The shallow and destructive Mw = 4.9 earthquake of 2018 December 26 occurred within the studied area two days after a dyke intrusion, that propagated beneath the centre of the volcano accompanied by a short eruption. Both GNSS and InSAR time-series document well those events and allow to investigate the post-seismic sliding across the faults of south-eastern flank. We analyse the slow slip events (SSE) that are observed in the GNSS and InSAR time-series in the vicinity of the Acitrezza fault. We quantify and discuss the tectonic origin of the Belpasso–Ognina lineament that we interpreted as a tear fault.

Alparone S., Barberi G., Bonforte A., Maiolino V., Ursino A., 2011; Evidence of multiple strain fields beneath the eastern flank of Mt. Etna volcano (Sicily, Italy) deduced from seismic and geodetic data during 2003-2004, Bull. Volcanol., 73(7), 869–885. 10.1007/s00445-011-0456-1
Google ScholarCrossrefSearch ADSWorldCat
Alparone S. C. et al. 2022. Mt. Etna Seismic Catalog 2017-2019 (EtnaSC_2017_2019) (Version 1) [Data set]. INGV Publication: Rome, Italy. doi:10.13127/ETNASC/2017_2019. 10.13127/ETNASC/2017_2019
Altamimi Z., Rebischung P., Métivier L., Collilieux X., 2016. ITRF2014: a new release of the International Terrestrial Reference Frame modeling nonlinear station motions. J. geophys. Res. Solid Earth, 121, 6109–6131. https://doi.org/10.1002/2016JB013098
Google ScholarCrossrefSearch ADSWorldCat
Antonioli F., Kershaw S., Rust D., Verrubbi V., 2003. Holocene sea-level change in Sicily and its implications for tectonic models: new data from the Taormina area, northeast Sicily. Mar. Geol., 196, 53–71. https://doi.org/10.1016/S0025-3227(03)00029-X
Google ScholarCrossrefSearch ADSWorldCat
Azzaro R., Branca S., Gwinner K., Coltelli M.: 2012; The volcano-tectonic map of Etna volcano, 1:100.000 scale: an integrated approach based on a morphotectonic analysis from high-resolution DEM constrained by geologic, active faulting and seismotectonic data, Ital. J. Geosci., 131(1), 153–170. 10.3301/IJG.2011.29.
Google ScholarCrossrefSearch ADSWorldCat
Belabbès S., Meghraoui M., Çakir Z., Bouhadad Y.: 2009; InSAR analysis of a blind thrust rupture and related active folding: the 1999 Ain Temouchent earthquake (M w 5.7, Algeria) case study, J. Seismol., 13(4), 421–432., https://doi.org 10.1007/s10950-008-9135-x.
Google ScholarCrossrefSearch ADSWorldCat
Berardino P., Fornaro G., Lanari R., Sansosti E.(2002). A new algorithm for surface deformation monitoring based on small baseline differential SAR interferograms. IEEE Trans. Geosci. Remote Sens., 40(11), 2375–2383., https://doi.org 10.1109/TGRS.2002.803792.
Google ScholarCrossrefSearch ADSWorldCat
Bertiger W. et al. 2020. GipsyX/RTGx, a new tool set for space geodetic operations and research. Adv. Space Res., 66, 469–489. https://doi.org/10.1016/j.asr.2020.04.015
Google ScholarCrossrefSearch ADSWorldCat
Boehm J., Niell A., Tregoning P., Schuh H., 2006. Global Mapping Function (GMF): a new empirical mapping function based on numerical weather model data. Geophys. Res. Lett., 33, L07304. doi:10.1029/2005GL025546​​​​​​. https://doi.org/10.1029/2005GL025546
Google ScholarCrossrefSearch ADSWorldCat
Bonaccorso A., Bonforte A., Guglielmino F., Palano M., Puglisi G.: 2006; Composite ground deformation pattern forerunning the 2004-2005 Mount Etna eruption, J. geophys. Res. Solid Earth, 111(B12), https://doi.org/10.1029/2005JB004206. doi:10.1029/2005JB004206
Google ScholarWorldCatCrossref
Bonforte A., Puglisi G.: 2006; Dynamics of the eastern flank of Mt. Etna volcano (Italy) investigated by a dense GPS network, J. Volc. Geotherm. Res., 153(3–4), 357–369. 10.1016/j.jvolgeores.2005.12.005 .
Google ScholarCrossrefSearch ADSWorldCat
Bonforte A., Bonaccorso A., Guglielmino F., Palano M., Puglisi G.: 2008; Feeding system and magma storage beneath Mt. Etna as revealed by recent inflation/deflation cycles, J. geophys. Res., 113(B5), B05406, doi:10.1029/2007JB005334 .10.1029/2007JB005334
Google ScholarCrossrefSearch ADSWorldCat
Bonforte A., Federico C., Giammanco S., Guglielmino F., Liuzzo M., Neri M.: 2013; Soil gases and SAR measurements reveal hidden faults on the sliding flank of Mt. Etna (Italy), J. Volc. Geotherm. Res., 251, 27–40. 10.1016/j.jvolgeores.2012.08.010
Google ScholarCrossrefSearch ADSWorldCat
Bonforte A., Guglielmino F., Coltelli M., Ferretti A., Puglisi G., 2011. Structural assessment of Mount Etna volcano from Permanent Scatterers analysis. Geochem. Geophys. Geosyst. 12, https://doi.org/10.1029/2010GC003213. 10.1029/2010GC003213
Google ScholarWorldCatCrossref
Bonforte A. et al. 2016. Global positioning system survey data for active seismic and volcanic areas of eastern Sicily, 1994 to 2013. Sci. Data, 3, 160062. https://doi.org/10.1038/sdata.2016.62. 10.1038/sdata.2016.62
Google ScholarCrossrefSearch ADSPubMedWorldCat
Bonforte A., Guglielmino F., Puglisi G., 2019; Large dyke intrusion and small eruption: the December 24, 2018 Mt. Etna eruption imaged by Sentinel-1 data, Terra Nova, 31, 405–412. 10.1111/ter.12403
Google ScholarCrossrefSearch ADSWorldCat
Borgia A. et al. 2000. Actively growing anticlines beneath catania from the distal motion of Mount Etna's Decollement measured by SAR interferometry and GPS. Geophys. Res. Lett., 27, 3409–3412. https://doi.org/10.1029/1999GL008475
Google ScholarCrossrefSearch ADSWorldCat
Bousquet J.-C., Lanzafame G., 1986. Déformations compressives quaternaires au bord sud de l'Etna. Comptes rendus l'Académie des Sci. Série 2, Mécanique, Phys. Chim. Sci. l'univers, Sci. la Terre. 235–240.
Google ScholarWorldCat
Branca S., De Guidi G., Lanzafame G., Monaco C., 2014; Holocene vertical deformation along the coastal sector of Mt. Etna volcano (eastern Sicily, Italy): implications on the time–space constrains of the volcano lateral sliding, J. Geodyn., 82, 194–203. 10.1016/j.jog.2014.07.006 .
Google ScholarCrossrefSearch ADSWorldCat
Brober K.B., 1999. Cracks and Fracture. Elsevier.
Google ScholarGoogle PreviewWorldCatCOPAC
Bruno V., Mattia M., Montgomery-Brown E., Rossi M., Scandura D., 2017. Inflation leading to a slow slip event and volcanic unrest at Mount Etna in 2016: insights from CGPS data. Geophys. Res. Lett., 44, 12,141-12,149. https://doi.org/10.1002/2017GL075744
Google ScholarWorldCat
Carnemolla F., 2021. What could be done to better monitor and understand the evolution of Etna faults? Monitoring and analysis of surface deformation using comparitive geodetic and topographyc techiniques. Case Study of the Eastern Slope of the Etna Volcano. PhD thesis, University of Catania.
Google ScholarGoogle PreviewWorldCatCOPAC
Casu F., Elefante S., Imperatore P., Zinno I., Manunta M., De Luca C., Lanari R., 2014. SBAS-DInSAR parallel processing for deformation time-series computation. IEEE J. Sel. Top. Appl. Earth Obs. Remote Sens., 7, 3285–3296. https://doi.org/10.1109/JSTARS.2014.2322671
Google ScholarCrossrefSearch ADSWorldCat
Catalano S., Torrisi S., Tortorici G., Romagnoli G., 2011. Active folding along a rift-flank: the Catania region case history (SE Sicily). J. Geodyn., 51, 53–63. https://doi.org/10.1016/j.jog.2010.08.001
Google ScholarCrossrefSearch ADSWorldCat
D'Agostino N., Avallone A., Cheloni D., D'Anastasio E., Mantenuto S., Selvaggi G., 2008. Active tectonics of the Adriatic region from GPS and earthquake slip vectors. J. geophys. Res. Solid Earth, 113, 1–19. https://doi.org/10.1029/2008JB005860
Google ScholarCrossrefSearch ADSWorldCat
D'Agostino N., Selvaggi G., 2004. Crustal motion along the Eurasia-Nubia plate boundary in the Calabrian Arc and Sicily and active extension in the Messina Straits from GPS measurements. J. geophys. Res. Solid Earth, 109, 1–16. https://doi.org/10.1029/2004JB002998
Google ScholarWorldCat
De Guidi G. et al. 2015. Geological, seismological and geodetic evidence of active thrusting and folding south of Mt. Etna (eastern Sicily): revaluation of “seismic efficiency” of the Sicilian Basal Thrust. J. Geodyn., 90, 32–41. https://doi.org/10.1016/j.jog.2015.06.001
Google ScholarCrossrefSearch ADSWorldCat
De Guidi G. et al. 2018. The unstable eastern flank of Mt. Etna volcano (Italy): first results of a GNSS-based network at its southeastern edge. J. Volc. Geotherm. Res., 357, 418–424. https://doi.org/10.1016/j.jvolgeores.2018.04.027
Google ScholarCrossrefSearch ADSWorldCat
De Guidi G., Catalano S., Monaco C., Tortorici L., 2003. Morphological evidence of Holocene coseismic deformation in the Taormina region (NE Sicily). J. Geodyn., 36, 193–211. https://doi.org/10.1016/S0264-3707(03)00047-4
Google ScholarCrossrefSearch ADSWorldCat
De Guidi G. et al. 2017. Brief communication: co-seismic displacement on 26 and 30 October 2016 (M w = 5.9 and 6.5)–earthquakes in central Italy from the analysis of a local GNSS network. Natural Hazards Earth Syst. Sci., 17(11), 1885–1892. https://doi.org/10.5194/nhess-17-1885-2017
Google ScholarCrossrefSearch ADSWorldCat
de Luca C. et al. 2015. An on-demand web tool for the unsupervised retrieval of earth's surface deformation from SAR data: the P-SBAS service within the ESA G-POD environment. Remote Sens., 7, 15630–15650. https://doi.org/10.3390/rs71115630
Google ScholarCrossrefSearch ADSWorldCat
De Michele M., Briole P.: 2007; Deformation between 1989 and 1997 at Piton de la Fournaise volcano retrieved from correlation of panchromatic airborne images, Geophys. J.. Int, 169, 357–364. 10.1111/j.1365-246X.2006.03307.x
Google ScholarCrossrefSearch ADSWorldCat
De Novellis V. et al. 2019; DInSAR analysis and analytical modeling of Mount Etna displacements: the December 2018 volcano-tectonic crisis, Geophys. Res. Lett., 46(11), 5817–5827. doi:10.1029/2019GL082467
Google ScholarCrossrefSearch ADSWorldCat
ESA, 2015. Geohazards-Thematic. Exploitation Platform [WWW Document]. URL https://geohazards-tep.eu (accessed 10.2.20).
Faccenna C. et al. 2011. Topography of the Calabria subduction zone (southern Italy): clues for the origin of Mt. Etna. Tectonics, 30. https://doi.org/10.1029/2010TC002694. 10.1029/2010TC002694
Google ScholarWorldCatCrossref
Firth C., Stewart I., Mcguire W.J., Kershaw S., Vita-Finzi C., 1996. Coastal elevation changes in eastern Sicily: implications for volcano instability at Mount Etna. Geol. Soc. Spec. Publ., 110, 153–167. https://doi.org/10.1144/GSL.SP.1996.110.01.12
Google ScholarCrossrefSearch ADSWorldCat
Froger J.L., Merle O., Briole P., 2001. Active spreading and regional extension at Mount Etna imaged by SAR interferometry. Earth planet. Sci. Lett., 187, 245–258. https://doi.org/10.1016/S0012-821X(01)00290-4
Google ScholarCrossrefSearch ADSWorldCat
Goes S., Jenny S., Hollenstein C., Kahle H.G., Geiger A., 2004. A recent tectonic reorganization in the south-central Mediterranean. Earth planet. Sci. Lett., 226, 335–345. https://doi.org/10.1016/j.epsl.2004.07.038
Google ScholarCrossrefSearch ADSWorldCat
Goldstein R. M., Werner C. L.: 1998; Radar interferogram filtering for geophysical applications, Geophys. Res. Lett., 25(21), 4035–4038. 10.1029/1998GL900033
Google ScholarCrossrefSearch ADSWorldCat
Hirn A. et al. 1997. Roots of Etna volcano in faults of great earthquakes. Earth Planet. Sci. Lett., 148, 171–191. https://doi.org/10.1016/s0012-821x(97)00023-x
Google ScholarCrossrefSearch ADSWorldCat
Huang M.-H. et al. 2006; A growing structure near the deformation front in SW Taiwan as deduced from SAR interferometry and geodetic observation, Geophys. Res. Lett., 33(12), L12305, doi:10.1029/2005GL025613.10.1029/2005GL025613
Google ScholarCrossrefSearch ADSWorldCat
Imposa S., De Guidi G., Grassi S., Scudero S., Barreca G., Patti G., Boso D.: 2015; Applying geophysical techniques to investigate a segment of a creeping fault in the urban area of San Gregorio di Catania, southern flank of Mt. Etna (Sicily - Italy), J. appl. Geophys., 123, 153–163. 10.1016/j.jappgeo.2015.10.008
Google ScholarCrossrefSearch ADSWorldCat
INGV RING Working Group, 2016. Rete Integrata Nazionale GNSS, http://ring.gm.ingv.it. 10.13127/RING
Crossref
Kershaw S., 2000. Quaternary reefs of Northeastern Sicily: structure and growth controls in an unstable tectonic setting. J. Coast. Res., 16, 1037–1062.
Google ScholarWorldCat
Labaume P., Claude Bousquet J., Lanzafame G., 1990. Early deformations at a submarine compressive front: the quaternary Catania foredeep south of Mt. Etna, Sicily, Italy. Tectonophysics, 177, 349–366. https://doi.org/10.1016/0040-1951(90)90395-O
Google ScholarCrossrefSearch ADSWorldCat
Lo Giudice E., Rasà R., 1992. Very shallow earthquakes and brittle deformation in active volcanic areas: the Eatnean region as an example. Tectonophysics, 202, 257–268. https://doi.org/10.1016/0040-1951(92)90111-I
Google ScholarWorldCat
Manunta M. et al. 2019. The parallel SBAS approach for Sentinel-1 interferometric wide swath deformation time-series generation: algorithm description and products quality assessment. IEEE Trans. Geosci. Remote Sens., 57, 6259–6281. https://doi.org/10.1109/TGRS.2019.2904912
Google ScholarCrossrefSearch ADSWorldCat
Mattia M. et al. 2015. A comprehensive interpretative model of slow slip events on Mt. Etna's eastern flank. Geochem. Geophys. Geosyst., 16, 635–658. https://doi.org/10.1002/2014GC005585
Google ScholarCrossrefSearch ADSWorldCat
Mattia M., Bruno V., Montgomery-Brown E., Patanè D., Barberi G., Coltelli M.: 2020; Combined seismic and geodetic analysis before, during, and after the 2018 Mount Etna Eruption, Geochem. Geophys. Geosyst., 21(9), 1–16. 10.1029/2020GC009218
Google ScholarCrossrefSearch ADSWorldCat
Monaco C. et al. 2021; The seismogenic source of the 2018 December 26th earthquake (Mt. Etna, Italy): a shear zone in the unstable eastern flank of the volcano, J. Geodyn., 143, 101807, doi:10.1016/j.jog.2020.101807.10.1016/j.jog.2020.101807
Google ScholarCrossrefSearch ADSWorldCat
Monaco C., Tapponnier P., Tortorici L., Gillot P.Y., 1997. Late Quaternary slip rates on the Acireale-Piedimonte normal faults and tectonic origin of Mt. Etna (Sicily). Earth Planet. Sci. Lett., 147, 125–139. https://doi.org/10.1016/s0012-821x(97)00005-8
Google ScholarCrossrefSearch ADSWorldCat
Monaco C., Tortorici L., 2000. Active faulting in the Calabrian arc and eastern Sicily. J. Geodyn., 29, 407–424. https://doi.org/10.1016/S0264-3707(99)00052-6
Google ScholarCrossrefSearch ADSWorldCat
Nishimura T., Tobita M., Yarai H., Amagai T., Fujiwara M., Une H., Koarai M.: 2008; Episodic growth of fault-related fold in northern Japan observed by SAR interferometry, Geophys. Res. Lett., 35(13), L13301, doi:10.1029/2008GL034337.10.1029/2008GL034337
Google ScholarCrossrefSearch ADSWorldCat
Palano M., 2016. Episodic slow slip events and seaward flank motion at Mt. Etna volcano (Italy). J. Volc. Geotherm. Res., 324, 8–14. https://doi.org/10.1016/j.jvolgeores.2016.05.010
Google ScholarCrossrefSearch ADSWorldCat
Palano M. et al. 2012. GPS velocity and strain fields in Sicily and southern Calabria, Italy: updated geodetic constraints on tectonic block interaction in the central Mediterranean. J. geophys. Res. Solid Earth, 117, https://doi.org/10.1029/2012JB009254. 10.1029/2012JB009254
Google ScholarWorldCatCrossref
Palano M., Sparacino F., Gambino P., D'Agostino N., Calcaterra S. (2022) Slow slip events and flank instability at Mt. Etna volcano (Italy). Tectonophysics, 836, 229414, doi:10.1016/J.TECTO.2022.229414.10.1016/J.TECTO.2022.229414
Google ScholarCrossrefSearch ADSGoogle PreviewWorldCatCOPAC
Pepe A., Yang Y., Manzo M., Lanari R.(2015). Improved EMCF-SBAS processing chain based on advanced techniques for the noise-filtering and selection of small baseline multi-look DInSAR interferograms. IEEE Trans. Geosci. Remote Sens., 53(8), 4394–4417. https://doi.org/10.1109/TGRS.2015.2396875
Google ScholarCrossrefSearch ADSWorldCat
Poland M. P., Peltier A., Bonforte A., Puglisi G.: 2017; The spectrum of persistent volcanic flank instability: a review and proposed framework based on Kīlauea, Piton de la Fournaise, and Etna, J. Volc. Geotherm. Res., 339, 63–80. 10.1016/j.jvolgeores.2017.05.004
Google ScholarCrossrefSearch ADSWorldCat
Rasà R., Azzaro R., Leonardi O., 1996. Aseismic creep on faults and flank instability at Mount Etna volcano, Sicily. Geol. Soc. Spec. Publ., 110, 179–192. https://doi.org/10.1144/GSL.SP.1996.110.01.14
Google ScholarCrossrefSearch ADSWorldCat
Regione Siciliana, 2010. Modello digitale del terreno (MDT) 2 m x 2 m Regione Siciliana-ATA 2007-2008. [WWW Document]. URL. http://www.sitr.regione.sicilia.it
Ristuccia G.M., Di Stefano A., Gueli A.M., Monaco C., Stella G., Troja S.O., 2013. OSL chronology of quaternary terraced deposits outcropping between Mt. Etna volcano and the Catania Plain (Sicily, southern Italy). Phys. Chem. Earth, 63, 36–46. https://doi.org/10.1016/j.pce.2013.03.002
Google ScholarCrossrefSearch ADSWorldCat
Rust D., Kershaw S., 2000. Holocene tectonic uplift patterns in northeastern Sicily: evidence from marine notches in coastal outcrops. Mar. Geol., 167, 105–126. https://doi.org/10.1016/S0025-3227(00)00019-0
Google ScholarCrossrefSearch ADSWorldCat
Schellart W.P.P., 2010. Mount Etna–Iblean volcanism caused by rollback-induced upper mantle upwelling around the Ionian slab edge: an alternative to the plume model. Geology, 38, 691–694. https://doi.org/10.1130/G31037.1
Google ScholarCrossrefSearch ADSWorldCat
Solaro G., Acocella V., Pepe S., Ruch J., Neri M., Sansosti E., 2010. Anatomy of an unstable volcano from InSAR: multiple processes affecting flank instability at Mt. Etna, 1994-2008. J. geophys. Res. Solid Earth, 115, 1994–2008. https://doi.org/10.1029/2009JB000820
Google ScholarCrossrefSearch ADSWorldCat
Spampinato C.R., Scicchitano G., Ferranti L., Monaco C., 2012. Raised Holocene paleo-shorelines along the Capo Schisò coast, Taormina: new evidence of recent co-seismic deformation in northeastern Sicily (Italy). J. Geodyn., 55, 18–31. https://doi.org/10.1016/j.jog.2011.11.007
Google ScholarCrossrefSearch ADSWorldCat
Stewart I.S., Cundy A., Kershaw S., Firth C., 1997. Holocene coastal uplift in the taormina area, northeastern sicily: implications for the southern prolongation of the calabrian seismogenic belt. J. Geodyn., 24, 37–50. https://doi.org/10.1016/S0264-3707(97)00012-4
Google ScholarCrossrefSearch ADSWorldCat
Tortorici L., Monaco C., Tansi C., Cocina O., 1995. Recent and active tectonics in the Calabrian arc (Southern Italy). Tectonophysics, 243, 37–55. https://doi.org/10.1016/0040-1951(94)00190-K
Google ScholarCrossrefSearch ADSWorldCat
Tringali G. et al. 2022. Fault rupture and aseismic creep accompanying the December 26, 2018, Mw 4.9 Fleri earthquake (Mt. Etna, Italy): factors affecting the surface faulting in a volcano-tectonic environment. Quat. Int. 651, 25–41., https://doi.org/10.1016/j.quaint.2021.12.019. 10.1016/J.QUAINT.2021.12.019
Google ScholarCrossrefSearch ADSWorldCat
Urlaub M. et al. 2018; Gravitational collapse of Mount Etna's southeastern flank, Sci. Adv., 4, 1–8. 10.1126/sciadv.aat9700
Google ScholarCrossrefSearch ADSWorldCat
Walsh J.J., Nicol A., Childs C., 2002. An alternative model for the growth of faults. J. Struct. Geol., 24, 1669–1675. https://doi.org/10.1016/S0191-8141(01)00165-1
Google ScholarCrossrefSearch ADSWorldCat
Westaway R., 1993. Quaternary uplift of southern Italy. J. geophys. Res., 98, 21741–21772. https://doi.org/10.1029/93jb01566

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