HR: 1330h
AN: T42B-0290    [PDF]
TI: Rising the Himalayan-Tibetan plateau: A 3-D finite element model
AU: * Yang, Y
EM: yangyo@missouri.edu
AF: University of Missouri, 101 Geology, Columbia, MO 65211 United States
AU: Liu, M
EM: lium@missouri.edu
AF: University of Missouri, 101 Geology, Columbia, MO 65211 United States
AB: More than 2000 km of the Earth's crust has been telescoped by the continuous Indo-Asian collision in the past 50-70 million years. Some models suggest that the shortened crustal material was taken up mainly by crustal thickening in the Himalayan-Tibetan Plateau and surrounding regions, whereas other models emphasize lateral extrusion of Asian continent along strike-slip faults as a way to accommodate the shortened crust. Here we present a fully three-dimensional finite element model to simulate the uplift history of Himalayan-Tibetan plateau. The model predicts a spatially variable pattern of uplift in the Himalayan-Tibetan Plateau even when a simple, flat pre-collision crust was assumed. The uplift generally propagated from south to north and from west to east. Most of the plateau reached the elevation of 3-km 10-20 Myr ago. Ductile flow in the lower crust is shown to be critical for producing the observed Tibetan topography. Inclusion of major strike-slip faults enhanced the lateral extrusion of the Asian continent. Partitioning of the shortened crustal material among thickening, lateral extrusion, and erosion changes with time. During the early history of the Indo-Asian collision, crustal thickening was the dominant mechanism for accommodating the telescoped crust material. However, its role peaked ~10 Myr ago, and lateral extrusion and erosion has become increasing important.
UR: http://www.missouri.edu/~yangyo
DE: 3230 Numerical solutions
DE: 8102 Continental contractional orogenic belts
DE: 8107 Continental neotectonics
DE: 8110 Continental tectonics--general (0905)
DE: 8150 Plate boundary--general (3040)
SC: Tectonophysics [T]
MN: 2003 Fall Meeting