HR: 09:45h
AN: T41E-08    [Abstracts]
TI: Earthquake Clustering along the Dead Sea Fault: The Influence of Strain Pattern and Geometrical Complexities on Rupture Propagation
AU: * Meghraoui, M
EM: mustapha@eost.u-strasbg.fr
AF: IPG Strasbourg, UMR 7516, 5, rue R. Descartes, Strasbourg, 67084, France
AB: The temporal clustering of large earthquakes is a salient characteristic of major continental faults in active zones. Interesting examples are large earthquake clusters along the East Anatolian fault (1820 – 1905), the North Anatolian fault (1912 – 1999), the Dead Sea fault (1137 – 1293), the southern San Andreas fault (1502 – 1680), the Kunlun Fault (1937 – 2001), the Tien Shan fault system (1885 – 1992) and Bulnay-Bogd fault system (1905 – 1957). Recent projects and faulting studies with paleoseismic investigations along the Dead Sea Fault (DSF) provided a wealth of field data and results on the physical characteristics of earthquake ruptures. Using individual and cumulative slip, and the rich historical seismicity catalogue and archeoseismic investigations along fault strike, I examine the length of earthquake rupture segments, the slip rate and timing of past earthquakes. The detailed mapping of rupture zones showing structural restraining bends, releasing step-overs, patch and segment boundaries, and slip distribution along strike illustrate their geometrical complexities. Taking into account the geologic and geodetic slip rate, I observe that the long-term behaviour of fault segments and/or patches determines the occurrence of seismic sequences and the location of seismic gaps. In addition to the slip deficit inferred from paleoseismic studies, two sections along the DSF shows seismic quiescence since nearly 1000 years and may be the location of near future earthquakes. In most cases, the clustering of large earthquakes migrate along fault segments and show off sequence seismic events. The mechanical coupling between off sequence distant earthquakes and laterally propagating ruptures depend mostly on the stress change at fault discontinuities and related block tectonics. The temporal clustering and multi-segment earthquakes ruptures in the past with coupling between step-overs and stress change suggests the size and probable length of future large earthquakes along major continental faults.
UR: http://apamea.u-strasbg.fr/
DE: 7221 Paleoseismology (8036)
DE: 7250 Transform faults
DE: 8036 Paleoseismology (7221)
DE: 8111 Continental tectonics: strike-slip and transform
SC: Tectonophysics [T]
MN: 2007 Fall Meeting