HR: 1340h
AN: T53B-0489    [Abstracts]
TI: Continental or Oceanic Crust? A new Study on the Crustal Structure of the Levantine Basin
AU: * Netzeband, G L
EM: netzeband@dkrz.de
AF: Institute of Geophysics University of Hamburg, Bundesstrasse 55, Hamburg, 20146 Germany
AU: Huebscher, C P
EM: huebscher@dkrz.de
AF: Institute of Geophysics University of Hamburg, Bundesstrasse 55, Hamburg, 20146 Germany
AU: Ben-Avraham, Z
EM: zvi@terra.tau.ac.il
AF: Tel Aviv University Department of Geophysics and Planetary Sciences, P.O.B. 39040, Ramat Aviv, Tel Aviv, 69978 Israel
AU: Gajewski, D
EM: gajeswki@dkrz.de
AF: Institute of Geophysics University of Hamburg, Bundesstrasse 55, Hamburg, 20146 Germany
AU: Gohl, K
EM: kgohl@awi-bremerhaven.de
AF: Alfred-Wegener-Institut f�r Polar- und Meeresforschung, Columbusstrasse, Bremerhaven, 27568 Germany
AU: Liersch, P
EM: liersch@dkrz.de
AF: Institute of Geophysics University of Hamburg, Bundesstrasse 55, Hamburg, 20146 Germany
AU: Wust-Bloch, H
EM: hillel@seismo.tau.ac.il
AF: Tel Aviv University Department of Geophysics and Planetary Sciences, P.O.B. 39040, Ramat Aviv, Tel Aviv, 69978 Israel
AB: The Levantine Basin in the Eastern Mediterranean Sea is a key area for understanding the closing of the Neo-Tethys. To unravel the origin and nature of the underlying crust Meteor cruise M52-2 was carried out in spring 2002. Two refraction seismic profiles were recorded, along with a net of multichannel seismic, gravity and magnetic lines. Two of the gravity and multichannel seimic lines coincide with the refraction profiles. Forward modelling of these profiles was carried out and the models show a Moho depth of 20 - 23km with a total crustal thickness of roughly 8km. The velocities of the upper crust are 6.0 - 6.3km/s, those of the lower crust 6.5 - 6.9km/s. Above lies a layer with 1 - 3km thickness and a velocity of 4.5km/s, which is covered by 5 - 7km of pre-Messinian sediments with an average velocity of 3.8km/s. On top of these sediments is an evaporite layer with a velocity of 4.3 - 4.4km/s, covered by young sediments of about 1km thickness and a water column of up to 1.5km. The gravity models support this structure and show additionally a steep decrease of the Moho depth down to almost 30km near the coast, without a change of velocity in the two crustal layers. Based on these velocity and density models and as a result of subsidence analysis we suggest the presence of continental crust beneath the Levantine Basin. The depth migrated nultichannel sections reveal recently active faults that cut through the entire evaporitic and post-Messinian sediment layer. This supports the thesis of active strike slip faults running subparallel to the DST.
DE: 8105 Continental margins and sedimentary basins
DE: 3010 Gravity
DE: 3025 Marine seismics (0935)
SC: Tectonophysics [T]
MN: 2004 AGU Fall Meeting