HR: 0800h
AN: T51C-1350    [Abstracts]
TI: Electrical Resistivity Structure of the Arabia-Eurasia Collision Zone in Eastern Anatolia
AU: * Turkoglu, E
EM: eturk@phys.ualberta.ca
AF: University of Alberta, Department of Physics, Edmonton, AB T6G 2J1 Canada
AU: Unsworth, M
EM: Unsworth@phys.uaberta.ca
AF: University of Alberta, Department of Physics, Edmonton, AB T6G 2J1 Canada
AU: Caglar, I
EM: caglari@itu.edu.tr
AF: Istanbul Technical University, Department of Geophysical Engineering, Istanbul, 80626 Turkey
AU: Tuncer, V
EM: vtuncer@phys.ualberta.ca
AF: University of Alberta, Department of Physics, Edmonton, AB T6G 2J1 Canada
AU: Avsar, U
EM: avsaru@itu.edu.tr
AF: Istanbul Technical University, Department of Geophysical Engineering, Istanbul, 80626 Turkey
AU: Tank, B
EM: bulent.tank@boun.edu.tr
AF: Bogazci University, Kandilli Observatory, ERI, Cengelkoy, Istanbul, 34342 Turkey
AU: Turkoglu, E
EM: eylemt@phys.ualberta.ca
AF: University of Alberta, Department of Physics, Edmonton, AB T6G 2J1 Canada
AU: Demir, T
EM: demirtun@itu.edu.tr
AF: Istanbul Technical University, Department of Geophysical Engineering, Istanbul, 80626 Turkey
AU: Sener, A
EM: senerah@itu.edu.tr
AF: Istanbul Technical University, Department of Geophysical Engineering, Istanbul, 80626 Turkey
AB: The tectonics of eastern Anatolia is dominated by the collision of the Arabian and Eurasian plates. Recent passive seismic exploration has provided new constraints on the seismic velocity structure of this region and suggest that asthenosphere may be present at shallow depth within the collision zone. Magnetotelluric data can provide independent constraints on processes in regions of active tectonics by remotely sensing the electrical resistivity of the crust and upper mantle. From May to November 2005 magnetotelluric (MT) data were collected in Eastern Anatolia in a joint Canadian-Turkish project by the University of Alberta and Istanbul Technical University. Long period MT data give penetration to upper mantle depths and were collected on profiles extending from the Arabian plate to the Black Sea with a spacing of 10-15 km. More detailed broadband MT data were collected on shorter profiles crossing the North and East Anatolian Fault Zones with a spacing of 1-2 km. Preliminary resistivity models will be presented for each of the profiles and indicate that: (1) A mid-crustal conductor is present beneath the Anatolian Block in the vicinity of Elazig and terminates directly beneath the surface trace of the East Anatolian Fault. This geometry is very similar to that observed on major strike-slip faults in Northern and Eastern Tibet. (2)East of the Karliova triple junction, the Anatolian crust has a high resistivity. A low resistivity zone is present at depths of 40-50 km and may represent a shallow asthenosphere. (3)Low resistivity is observed in the upper mantle beneath Karacadag, a center of recent basaltic eruptions on the Arabian Plate, and in the crust beneath the Nemrut Golu - Suphan Dagi volcanic belt. The tectonic significance of these new MT data will be discussed in the context of other geological and geophysical data.
DE: 8031 Rheology: crust and lithosphere (8159)
DE: 8104 Continental margins: convergent
DE: 8110 Continental tectonics: general (0905)
DE: 8111 Continental tectonics: strike-slip and transform
SC: Tectonophysics [T]
MN: Fall Meeting 2005