TY  - JOUR
A1  - Braeuer, B.
A1  - Asch, Günter
A1  - Hofstetter, Rami
A1  - Haberland, Christian
A1  - Jaser, Darweesh
A1  - El-Kelani, Radwan J..
A1  - Weber, Michael H.
T1  - Microseismicity distribution in the southern Dead Sea basin and its implications on the structure of the basin
JF  - Geophysical journal international
N2  - While the Dead Sea basin has been studied for a long time, the available knowledge about the detailed seismicity distribution in the area, as well as the deeper structure of the basin, is limited. Therefore, within the framework of the international project DESIRE (DEad Sea Integrated REsearch project), a dense temporary local seismological network was operated in the southern Dead Sea area. We use 530 local earthquakes, having all together 26 730 P- and S-arrival times for a simultaneous inversion of 1-D velocity models, station corrections and precise earthquake locations. Jackknife tests suggest an accuracy of the derived hypocentre locations of about 1 km. Thus, the result is the first clear image of the absolute distribution of the microseismicity of the area, especially in depth. The seismicity is concentrated in the upper crust down to 20 km depth while the lower limit of the seismicity is reached at 31 km depth. The seismic events at the eastern boundary fault (EBF) in the southern part of the study area represent the northward transform motion of the Arabian Plate along the Dead Sea Transform. North of the Boqeq fault the seismic activity represents the transfer of the motion in the pull-apart basin from the eastern to the western boundary. We find that from the surface downward the seismic events are tracing the boundary faults of the basin. The western boundary is mapped down to 12 km depth while the EBF reaches about 17 km depth, forming an asymmetric basin. One fifth of the data set is related to a specific cluster in time and space, which occurred in 2007 February at the western border fault. This cluster is aligned vertically, that is, it is perpendicular to the direction of the dominating left-lateral strike-slip movement at the main transform fault.
KW  - Seismicity and tectonics
KW  - Continental tectonics: strike-slip and transform
KW  - Asia
Y1  - 2012
U6  - https://doi.org/10.1111/j.1365-246X.2011.05318.x
SN  - 0956-540X
VL  - 188
IS  - 3
SP  - 873
EP  - 878
PB  - Wiley-Blackwell
CY  - Malden
ER  - 
TY  - JOUR
A1  - Weber, Michael H.
A1  - Abu-Ayyash, Khalil
A1  - Abueladas, Abdel-Rahman
A1  - Agnon, Amotz
A1  - Alasonati-Tašárová, Zuzana
A1  - Al-Zubi, Hashim
A1  - Babeyko, Andrey
A1  - Bartov, Yuval
A1  - Bauer, Klaus
A1  - Becken, Michael
A1  - Bedrosian, Paul A.
A1  - Ben-Avraham, Zvi
A1  - Bock, Günter
A1  - Bohnhoff, Marco
A1  - Bribach, Jens
A1  - Dulski, Peter
A1  - Ebbing, Joerg
A1  - El-Kelani, Radwan J.
A1  - Foerster, Andrea
A1  - Förster, Hans-Jürgen
A1  - Frieslander, Uri
A1  - Garfunkel, Zvi
A1  - Götze, Hans-Jürgen
A1  - Haak, Volker
A1  - Haberland, Christian
A1  - Hassouneh, Mohammed
A1  - Helwig, Stefan L.
A1  - Hofstetter, Alfons
A1  - Hoffmann-Rothe, Arne
A1  - Jaeckel, Karl-Heinz
A1  - Janssen, Christoph
A1  - Jaser, Darweesh
A1  - Kesten, Dagmar
A1  - Khatib, Mohammed Ghiath
A1  - Kind, Rainer
A1  - Koch, Olaf
A1  - Koulakov, Ivan
A1  - Laske, Maria Gabi
A1  - Maercklin, Nils
T1  - Anatomy of the Dead Sea transform from lithospheric to microscopic scale
N2  - Fault zones are the locations where motion of tectonic plates, often associated with earthquakes, is accommodated. Despite a rapid increase in the understanding of faults in the last decades, our knowledge of their geometry, petrophysical properties, and controlling processes remains incomplete. The central questions addressed here in our study of the Dead Sea Transform (DST) in the Middle East are as follows: (1) What are the structure and kinematics of a large fault zone? (2) What controls its structure and kinematics? (3) How does the DST compare to other plate boundary fault zones? The DST has accommodated a total of 105 km of left-lateral transform motion between the African and Arabian plates since early Miocene (similar to 20 Ma). The DST segment between the Dead Sea and the Red Sea, called the Arava/Araba Fault (AF), is studied here using a multidisciplinary and multiscale approach from the mu m to the plate tectonic scale. We observe that under the DST a narrow, subvertical zone cuts through crust and lithosphere. First, from west to east the crustal thickness increases smoothly from 26 to 39 km, and a subhorizontal lower crustal reflector is detected east of the AF. Second, several faults exist in the upper crust in a 40 km wide zone centered on the AF, but none have kilometer-size zones of decreased seismic velocities or zones of high electrical conductivities in the upper crust expected for large damage zones. Third, the AF is the main branch of the DST system, even though it has accommodated only a part (up to 60 km) of the overall 105 km of sinistral plate motion. Fourth, the AF acts as a barrier to fluids to a depth of 4 km, and the lithology changes abruptly across it. Fifth, in the top few hundred meters of the AF a locally transpressional regime is observed in a 100-300 m wide zone of deformed and displaced material, bordered by subparallel faults forming a positive flower structure. Other segments of the AF have a transtensional character with small pull-aparts along them. The damage zones of the individual faults are only 5-20 m wide at this depth range. Sixth, two areas on the AF show mesoscale to microscale faulting and veining in limestone sequences with faulting depths between 2 and 5 km. Seventh, fluids in the AF are carried downward into the fault zone. Only a minor fraction of fluids is derived from ascending hydrothermal fluids. However, we found that on the kilometer scale the AF does not act as an important fluid conduit. Most of these findings are corroborated using thermomechanical modeling where shear deformation in the upper crust is localized in one or two major faults; at larger depth, shear deformation occurs in a 20-40 km wide zone with a mechanically weak decoupling zone extending subvertically through the entire lithosphere.
Y1  - 2009
UR  - http://www.agu.org/journals/rg/
U6  - https://doi.org/10.1029/2008rg000264
SN  - 8755-1209
ER  -