HR: 0800h
AN: T41A-1271 [Abstracts]
TI: Lithosperic Image Across the Eastern Tian Shan Mountains from Migrated Receiver Functions
AU: * Li, H
EM: li_hai_ou@126.com
AF: China University of Geosciences (Beijing), 29 Xueyuan Road, Haidian District, Beijing, 100083
China
AU: Jiao, W
EM: wjiao@multimax.com
AF: Multimax Inc., 1441 McCormick Drive, Largo, MD 20774
United States
AU: Chan, W
EM: winston@multimax.com
AF: Multimax Inc., 1441 McCormick Drive, Largo, MD 20774
United States
AB:
To the north of the Tibetan plateau, a series of mountain ranges were built under the compression from the Indian plate where
Tian Shan Mountains are situated between the Kunlun/Altyn Mountains to the south, and the Altai Mountains to the north. Also
situated between these mountain ranges are large cratonic basins. The topography changes drastically across the eastern Tian
Shan Mountains, with Turfan basin in the southern front being the lowest point in China. Several large, deep fault zones
were suggested to have ruptured into the mantle. In order to get a better picture of the Moho and these fault zones, we
processed a seismic profile 700km in length across the eastern Tian Shan Mountains consisting of 39 portable and 8 permanent
seismic stations. 172 receiver functions were migrated to produce an image of the lithosphere in the profile. The Moho depth
is mapped across the profile. Under the Dzungarian basin to the north of the Tian Shan Mountains, the Moho is gently tilted
southward, from about 40km to 60km. Under the eastern Tian Shan Mountains, the Moho is downward convex, with the lowest depth
around 70km. In this part of the profile it is also clearly seen that the Moho is ruptured by several thrust fault zones.
Under the Northern Tian Shan fault, the image shows a clear overlap of the Moho due to overthrusting, where the most active
seismic zone is situated. Our results are different in some details from the previous profile studies to the west of our
profile.
DE: 7200 SEISMOLOGY
DE: 7218 Lithosphere (1236)
DE: 8100 TECTONOPHYSICS
DE: 8120 Dynamics of lithosphere and mantle: general (1213)
SC: Tectonophysics [T]
MN: Fall Meeting 2005