Seismicity, deformation and seismic hazard in the western rift of Corinth: New insights from the Corinth Rift Laboratory (CRL)

Bernard, P; Lyon-Caen, H; Briole, P; Deschamps, A; Boudin, F; Makropoulos, K; Papadimitriou, P; Lemeille, F; Patau, G; Billiris, H; Paradissis, D; Papazissi, K; Castarede, H; Charade, O; Nercessian, A; Avallone, A; Pacchiani, F; Zahradnik, J; Sacks, S; Linde, A

dc.contributor.author	Bernard, P	en
dc.contributor.author	Lyon-Caen, H	en
dc.contributor.author	Briole, P	en
dc.contributor.author	Deschamps, A	en
dc.contributor.author	Boudin, F	en
dc.contributor.author	Makropoulos, K	en
dc.contributor.author	Papadimitriou, P	en
dc.contributor.author	Lemeille, F	en
dc.contributor.author	Patau, G	en
dc.contributor.author	Billiris, H	en
dc.contributor.author	Paradissis, D	en
dc.contributor.author	Papazissi, K	en
dc.contributor.author	Castarede, H	en
dc.contributor.author	Charade, O	en
dc.contributor.author	Nercessian, A	en
dc.contributor.author	Avallone, A	en
dc.contributor.author	Pacchiani, F	en
dc.contributor.author	Zahradnik, J	en
dc.contributor.author	Sacks, S	en
dc.contributor.author	Linde, A	en
dc.date.accessioned	2014-03-01T01:25:08Z
dc.date.available	2014-03-01T01:25:08Z
dc.date.issued	2006	en
dc.identifier.issn	0040-1951	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/17552
dc.subject	Deformation	en
dc.subject	Gulf of Corinth	en
dc.subject	Normal faulting	en
dc.subject	Rifting	en
dc.subject	Seismic Hazard	en
dc.subject	Seismicity	en
dc.subject.classification	Geochemistry & Geophysics	en
dc.subject.other	active fault	en
dc.subject.other	deformation	en
dc.subject.other	earthquake magnitude	en
dc.subject.other	geophysical survey	en
dc.subject.other	normal fault	en
dc.subject.other	seismic hazard	en
dc.subject.other	seismicity	en
dc.subject.other	Gulf of Corinth	en
dc.subject.other	Ionian Sea	en
dc.subject.other	Mediterranean Sea	en
dc.title	Seismicity, deformation and seismic hazard in the western rift of Corinth: New insights from the Corinth Rift Laboratory (CRL)	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/j.tecto.2006.02.012	en
heal.identifier.secondary	http://dx.doi.org/10.1016/j.tecto.2006.02.012	en
heal.language	English	en
heal.publicationDate	2006	en
heal.abstract	This paper presents the main recent results obtained by the seismological and geophysical monitoring arrays in operation in the rift of Corinth, Greece. The Corinth Rift Laboratory (CRL) is set up near the western end of the rift, where instrumental seismicity and strain rate is highest. The seismicity is clustered between 5 and 10 km, defining an active layer, gently dipping north, on which the main normal faults, mostly dipping north, are rooting. It may be interpreted as a detachment zone, possibly related to the Phyllade thrust nappe. Young, active normal faults connecting the Aigion to the Psathopyrgos faults seem to control the spatial distribution of the microseismicity. This seismic activity is interpreted as a seismic creep from GPS measurements, which shows evidence for fast continuous slip on the deepest part on the detachment zone. Offshore, either the shallowest part of the faults is creeping, or the strain is relaxed in the shallow sediments, as inferred from the large NS strain gradient reported by GPS. The predicted subsidence of the central part of the rift is well fitted by the new continuous GPS measurements. The location of shallow earthquakes (between 5 and 3.5 km in depth) recorded on the on-shore Helike and Aigion faults are compatible with 50 degrees and 60 degrees mean dip angles, respectively. The offshore faults also show indirect evidence for high dip angles. This strongly differs from the low dip values reported for active faults more to the east of the rift, suggesting a significant structural or theological change, possibly related to the hypothetical presence of the Phyllade nappe. Large seismic swarms, lasting weeks to months, seem to activate recent synrift as well as pre-rift faults. Most of the faults of the investigated area are in their latest part of cycle, so that the probability of at least one moderate to large earthquake (M = 6 to 6.7) is very high within a few decades. Furthermore, the region west to Aigion is likely to be in an accelerated state of extension, possibly 2 to 3 times its mean interseismic value. High resolution strain measurement, with a borehole dilatometer and long base hydrostatic tiltmeters, started end of 2002, A transient strain has been recorded by the dilatometer, lasting one hour, coincident with a local magnitude 3.7 earthquake. It is most probably associated with a slow slip event of magnitude around 5 +/- 0.5. The pore pressure data from the 1 km deep AIG10 borehole, crossing the Aigion fault at depth, shows a 1 MPa overpressure and a large sensitivity to crustal strain changes. (c) 2006 Elsevier B.V All rights reserved.	en
heal.publisher	ELSEVIER SCIENCE BV	en
heal.journalName	Tectonophysics	en
dc.identifier.doi	10.1016/j.tecto.2006.02.012	en
dc.identifier.isi	ISI:000241719400002	en
dc.identifier.volume	426	en
dc.identifier.issue	1-2	en
dc.identifier.spage	7	en
dc.identifier.epage	30	en