HR: 09:45h
AN: S21C-08    [Abstracts]
TI: Integrated study of seismicity and subsurface geology (Arava valley)
AU: * Rybakov, M
EM: rybakov@gii.co.il
AF: Geophysical Institute of Israel, 6 Habaal Shem Tov, Lod, 71100 Israel
AU: ten Brink, U
EM: utenbrink@usgs.gov
AF: U.S. Geological Survey, 384 Woods Hole Rd., Woods Hole, MA 02543 United States
AU: Al-Zoubi, A
EM: aalzoubi@go.com.jo
AF: Al-Balqa Applied University, Al-Salt, Al-Salt, 19117 Jordan
AU: Kraeva, N
EM: nadia@seis.mni.gov.il
AF: Geophysical Institute of Israel, 6 Habaal Shem Tov, Lod, 71100 Israel
AU: Rami Hofstetter, A
EM: rami@seis.mni.gov.il
AF: Geophysical Institute of Israel, 6 Habaal Shem Tov, Lod, 71100 Israel
AB: The spatial distribution of the earthquakes in the Arava Valley, a 150-km-section of the Dead Sea Transform, is compared with the local subsurface geological features derived from geophysical and geological data. Gravity data suggested that the Gharandal, Timna and Elat Basins were filled by low-density young sediments. These features were confirmed by seismic reflection profiles and high resolution low altitude aeromagnetic (HRAM) survey. The HRAM survey delineated the trace of the Dead Sea Transform in this region, which separates magnetic anomalies in the eastern and western parts of the valley, and revealed the occurrence of the hitherto unknown deep magmatics. Overall the earthquake activity appears to be strongly related to the Dead Sea Transform. However, on a local scale, there is no apparent correlation between the seismicity and the fault segments comprising the DST fault system. Absence of the correlation may be explained as result of insufficient accuracy (about of 4 km) of the earthquake localization and /or inclined fault plane. However, in spite of such inaccuracy, there is clearly observed that clusters of the earthquakes coincide with the sedimentary basins. Two pronounced clusters appear to coincide with the subsurface magmatics. We assume that the subsurface geology affects areas of stress concentration and hence of earthquakes. These areas can be the end of faults, or fault jogs, which sometimes create basins, or areas of heterogeneous rheology, such as in the vicinity of magmatic bodies.
UR: http://www.svmatch.com/
DE: 1219 Gravity anomalies and Earth structure (0920, 7205, 7240)
DE: 1517 Magnetic anomalies: modeling and interpretation
DE: 7230 Seismicity and tectonics (1207, 1217, 1240, 1242)
DE: 8015 Local crustal structure
SC: Seismology [S]
MN: Fall Meeting 2005