HR: 08:00h
AN: S41E-01    [Abstracts]
TI: Crust and Upper Mantle of North Africa Using Libyan Seismic Data
AU: * Pasyanos, M E
EM: pasyanos1@llnl.gov
AF: Lawrence Livermore National Laboratory, P.O. Box 808 L -205, Livermore, CA 94551 United States
AU: Eshwehdi, A
EM: eshwehdi@yahoo.com
AF: Libyan Digital Seismological Network, P.O. Box 82245, Tripoli, 82245 Libyan Arab Jamahiriya
AB: We investigate the crust and upper mantle structure of North Africa using Libyan seismic data. Libya sits at the transition between the relatively aseismic continental crust of the African plate and the seismically active oceanic crust under the Mediterranean Sea which is subducting under the Eurasian Plate along the Calabrian, Hellenic, and Cyprean Arcs. The country also encompasses the Sirte Basin to the north and the smaller Murzuk and Kufra basins in the south. Broadband data from several seismic stations in Libya provide an opportunity for studying the velocity structure of the region. We have made some preliminary dispersion measurements from these stations and have found notable improvements in the group velocity tomography model by incorporating the additional measurements. We will be adding to this analysis by making dispersion measurements from regional events and receiver functions for teleseismic events. Recently, we have been employing methods to jointly invert both surface wave dispersion data and teleseismic receiver functions. The technique holds great promise in accurately estimating seismic structure, including important tectonic parameters such as basin thickness, crustal thickness, upper mantle velocity, as well as more detail about the upper mantle (lithospheric thickness and presence of anisotropy). We propose to apply this method to data from several Libyan stations where we can and, in the absence of receiver functions, invert the dispersion data only. The technique holds the promise of improving our understanding of the crust and upper mantle in Libya and how it fits into the larger tectonic picture of North Africa.
DE: 7203 Body waves
DE: 7205 Continental crust (1219)
DE: 7208 Mantle (1212, 1213, 8124)
DE: 7218 Lithosphere (1236)
DE: 7255 Surface waves and free oscillations
SC: Seismology [S]
MN: Fall Meeting 2005