Crustal Structure Along The DESERT 2000 Transect Inferred From 3-D Gravity Modelling

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Journal Title, Volume, Page: 
American Geophysical Union, Fall Meeting 2003, abstract #S21F-0399
Year of Publication: 
Radwan J. El-Kelani
Earth Sciences and Seismic Engineering Center (ESSEC), An-Najah National University, P.O. Box 707, Nablus, Palestine
Goetze, H
Institut fuer Geologie, Geophysik und Geoinformatik, FU Berlin, Malteserstr. 74-100, Haus N, Berlin, 12249 Germany
Rybakov, M
Hassouneh, M
Natural Resources Authority, P.O. Box 7, Amman, 11118 Jordan
Schmidt, S
Institut fuer Geologie, Geophysik und Geoinformatik, FU Berlin, Malteserstr. 74-100, Haus N, Berlin, 12249 Germany
Preferred Abstract (Original): 

A three-dimensional interpretation of the newly compiled Bouguer anomaly map is part of the DESERT 2000 Transect. That is multi-disciplinary and multinational project studying for first time the Dead Sea Transform (DST) fault system (DST) from the Mediterranean Sea to Saudi Arabia across the international border in the NW-SE direction. The negative Bouguer anomalies (with magnitude reached "C130 mGal), located into transform valley, are caused by the internal sedimentary basins filled by the light density young sediments (­Y10 km). A high-resolution 3-D model constrained with the seismic results reveals a possible crustal thickness and density distribution beneath the DST valley. The inferred zone of intrusion coincides with the maximum gravity anomaly over the eastern flank of the DST. The intrusion is displaced at different sectors along the NW-SE direction. The zone of the maximum crustal thinning (­š30 km) is attained in the western sector at the Mediterranean. The southeastern plateau, on the other hand, shows by far the largest crustal thickness in the region (38-42 km). Linked to the left lateral movement of ~ 105 km at the boundary between the African and Arabian plate, and constrained with the DESERT 2000 seismic data, a small asymmetric topography of the Moho beneath the DST was modelled. The thickness and density of the crust suggest that a continental crust underlies the DST. The deep basins, the relatively large nature of the intrusion and the asymmetric topography of the Moho lead to the conclusion that a small-scale asthenospheric upwelling(?) might be responsible for the thinning of the crust and subsequent rifting of the Dead Sea graben during the left lateral movement.