Development of a procedure for correcting and reducing unwrapping artefacts using a set of ERS SAR interferograms. Case of the September 7, 1999 Athens Earthquake

Elias, P; Sykioti, O; Kontoes, C; Avallone, A; Van Gorp, S; Briole, P; Paradissis, D

dc.contributor.author	Elias, P	en
dc.contributor.author	Sykioti, O	en
dc.contributor.author	Kontoes, C	en
dc.contributor.author	Avallone, A	en
dc.contributor.author	Van Gorp, S	en
dc.contributor.author	Briole, P	en
dc.contributor.author	Paradissis, D	en
dc.date.accessioned	2014-03-01T02:49:44Z
dc.date.available	2014-03-01T02:49:44Z
dc.date.issued	2004	en
dc.identifier.issn	03796566	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/34719
dc.relation.uri	http://www.scopus.com/inward/record.url?eid=2-s2.0-18644383664&partnerID=40&md5=d76beb80c5e463addafb23a4bb7ba8ba	en
dc.subject.other	Co-seismic interferograms	en
dc.subject.other	Faults	en
dc.subject.other	Interferometric synthetic aperture radar (InSAR)	en
dc.subject.other	Radar interferometry	en
dc.subject.other	Computer software	en
dc.subject.other	Deformation	en
dc.subject.other	Earthquakes	en
dc.subject.other	Geodetic satellites	en
dc.subject.other	Geographical regions	en
dc.subject.other	Interferometers	en
dc.subject.other	Seismic prospecting	en
dc.subject.other	Tectonics	en
dc.subject.other	Synthetic aperture radar	en
dc.title	Development of a procedure for correcting and reducing unwrapping artefacts using a set of ERS SAR interferograms. Case of the September 7, 1999 Athens Earthquake	en
heal.type	conferenceItem	en
heal.publicationDate	2004	en
heal.abstract	On September 7, 1999 a magnitude Mw=5.9 earthquake occurred in the Athens area (Greece) producing a subsidence of about 6 cm detected by radar interferometry. Using seventeen ERS SAR images acquired between December 1997 and January 2001, one hundred thirty six interferograms of the area have been calculated using the CNES DIAPASON software. Among them, eighty-one have been selected on the basis of coherence and used in the processing. These interferograms have been used to produce a collective coherence map and they have been unwrapped using the SNAPHU software. Orbital effects have been reduced by tilting and shifting the unwrapped interferograms, making the assumption that no deformation has occurred in zones located at the edges of the scene, which are far away from the area affected by the earthquake. This procedure was applied constraining the deformation value of the most coherent pixels in the selected zones to a zeroed value. Twenty-four co-seismic, five pre-seismic and eight post-seismic interferograms have been finally selected on the basis of the coherence of the phase signal. The co-seismic interferograms have been stacked to produce a smoothed image of the average deformation field. The resulted deformation field is used to recalculate the deformation source and to produce a new model, which is found to be close to that proposed by Kontoes et al., 2000. The synthetic interferogram issued from the model is then subtracted from each co-seismic interferogram. The corrected residuals of the co-seismic interferograms and the corrected pre- and post-seismic interferograms are finally examined to detect any temporal evolution of the deformation before and after the main event.	en
heal.journalName	European Space Agency, (Special Publication) ESA SP	en
dc.identifier.issue	550	en
dc.identifier.spage	417	en
dc.identifier.epage	423	en