Deformation feature of the Asian continent

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The Indian subcontinent collided with the Asian continent and subsequently penetrated into southern Asia. Collision and penetration of tectonic blocks resulted in large scale deformation in the Asian continent. The mode of tectonic deformation of the Asian continent has been widely debated during the last two decades. The Asian continent is regarded to behave as either a deforming continuum material or as an assemblage of rigid bodies. In the continuum model, penetrated material in Asia due to intrusion of India is absorbed by crustal thickening beneath the Tibetan plateau and by tectonic rotation of crust along both sides of India. The rigid body model stresses that major strike-slip faults play an important role in accommodating the deformation between India and Asia, and that the regions between the major faults move as rigid blocks. Recently the relative importance of these two modes has been tested through velocity field determination of the Asian continent using Holocene geologic record and geodetic information from GPS data.An alternative method for evaluating the style of deformation within the Asian continent is paleomagnetism. We collected Jurassic to Paleogene redsanstones from Tibet, Indochina and Yangtze blocks during the last three years. Post-Cretaceous clockwise rotation of the crustal blocks was observed over a broad area that extends from eastern Tibet through South China to Indochina in this study. Large-scale southeastward displacement was also suggested for Indochina block and Simao block. Paleomagnetic data from the Yangtze, Indochina and Simao blocks offer an opportunity to better understand the intracontinetnal deformation of the Asian continent.