In September 1999, a moderate (M(W) = 5.9) earthquake struck the Attica plain, causing unexpected and extensive damage to Athens and its population. In this work, we exploit the potential of multitemporal Differential Interferometry by Synthetic Aperture Radar (DInSAR) analysis, using about a hundred European Remote Sensing (ERS) 1/2 images to calculate the displacement time series from 1992 to 2002. This analysis allows us to clearly separate a strictly coseismic signal from a postseismic gradual subsidence, reaching a maximum value of about 3 cm in the following 2.5 years. We model this signal in terms of afterslip on the seismogenic fault. The afterslip distribution, retrieved by linear inversion, reflects the coseismic slip distribution and occurs mainly downdip of the area that ruptured during the main shock. The analysis of the static stress transfer suggests that the afterslip was triggered by the main shock, then it propagated aseismically through the fault plane. A partial overlap between the coseismic and aseismic slip area at the hypocentral region indicates that the 1999 rupture surface was not "healed'' at least until the date of the last postseismic image (April 2002). The results obtained with a time series approach for this moderate magnitude earthquake suggest that multitemporal DInSAR analysis should become an important methodology for the study of large earthquake ruptures. RI Salvi, Stefano/G-3905-2011

Postseismic displacement of the 1999 Athens earthquake retrieved by the Differential Interferometry by Synthetic Aperture Radar time series

MANUNTA, MICHELE;
2008-01-01

Abstract

In September 1999, a moderate (M(W) = 5.9) earthquake struck the Attica plain, causing unexpected and extensive damage to Athens and its population. In this work, we exploit the potential of multitemporal Differential Interferometry by Synthetic Aperture Radar (DInSAR) analysis, using about a hundred European Remote Sensing (ERS) 1/2 images to calculate the displacement time series from 1992 to 2002. This analysis allows us to clearly separate a strictly coseismic signal from a postseismic gradual subsidence, reaching a maximum value of about 3 cm in the following 2.5 years. We model this signal in terms of afterslip on the seismogenic fault. The afterslip distribution, retrieved by linear inversion, reflects the coseismic slip distribution and occurs mainly downdip of the area that ruptured during the main shock. The analysis of the static stress transfer suggests that the afterslip was triggered by the main shock, then it propagated aseismically through the fault plane. A partial overlap between the coseismic and aseismic slip area at the hypocentral region indicates that the 1999 rupture surface was not "healed'' at least until the date of the last postseismic image (April 2002). The results obtained with a time series approach for this moderate magnitude earthquake suggest that multitemporal DInSAR analysis should become an important methodology for the study of large earthquake ruptures. RI Salvi, Stefano/G-3905-2011
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11584/69213
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 48
  • ???jsp.display-item.citation.isi??? 45
social impact