HR: 0830h
AN: GP11A-0251    [PDF]
TI: The electrical image of the Dead Sea Transform on a regional scale
AU: * Weckmann, U
EM: uweck@gfz-potsdam.de
AF: GeoForschungsZentrum, Telegrafenberg, Potsdam, 14473 Germany
AU: Ritter, O
EM: oritter@gfz-potsdam.de
AF: GeoForschungsZentrum, Telegrafenberg, Potsdam, 14473 Germany
AU: Hoffmann-Rothe, A
EM: ahoro@gfz-potsdam.de
AF: GeoForschungsZentrum, Telegrafenberg, Potsdam, 14473 Germany
AU: Abueladas, A
EM: abueladas@hotmail.com
AF: Natural Resources Authority, P.O. Box 7, Amman, 11118 Jordan
AU: Haak, V
EM: vhaak@gfz-potsdam.de
AF: GeoForschungsZentrum, Telegrafenberg, Potsdam, 14473 Germany
AB: The trans-continental Dead Sea Transform (DST) forms the boundary between the African and Arabian plates in the Middle East and connects the Red Sea rift in the south with the Alpine orogenic belt in Turkey. The aim of the multi-disciplinary DESERT project is to study this plate tectonic setting on all scales and to better understand its dynamics in the Earth crust and upper mantle. The experiment was conducted in the Arava valley, where strike-slip displacement seems to be concentrated on a distinct and continuous master fault . We present magnetotelluric (MT) data from 82 sites collected in 2002 along a 100 km long east-west striking profile. This profile follows a seismic reflection / refraction line in Jordan, from the border to Israel, crossing the escarpment of the Edom Mountains to Ma'an in the east. 2D conductivity models of MT data collected in 2000 and 2001 along short profiles in the Arava valley revealed a strong lateral conductivity contrast in form of a conductive half layer west of the DST in1.5 km depth with a sharp vertical conductivity boundary directly beneath its surface trace. The short profile lengths, however, restrict the interpretation to a depth of approximately 5km. With this new MT data set we are now able to model the conductivity structure of the entire crust. The regional 2D inversion models indicate that the zone of anomalously high conductivity associated with the DST could extend down to mid-crustal depth. The area east of the fault in the Arava valley shows intermediate resistivities which can possibly be explained by fractured Precambrian rocks overlain by sediments. The escarpment of the Edom Mountains as well as the plateau is dominated by a generally resistive subsurface. At the edge of the plateau we identify the branches of the Al Quwayra fault system as shallow conductive anomalies. In the eastern part of the profile near Ma'an we resolve the Mesozoic and Cenozoic sedimentary cover that increases in thickness further to the north.
DE: 1515 Geomagnetic induction
DE: 8010 Fractures and faults
DE: 8100 TECTONOPHYSICS
DE: 8110 Continental tectonics--general (0905)
DE: 9320 Asia
SC: Geomagnetism and Paleomagnetism [GP]
MN: 2003 Fall Meeting