ANALYSIS OF CONTEMPORARY CRUSTAL DEFORMATIONCHARACTERISTICS WITH GPS DATA OF TIANSHAN MOUNTAIN
Niu Zhijun 1,2) ;You Xinzhao 2) ; and Yang Shaomin 3)
1)Huazhong University of Science and Technology,Wuhan 4300742)National Earthquake Infrastructure Service,Beijing 1000633)Institute of Seismology,CEA,Wuhan 430071
Abstract Using the GPS data which is collected from 382 observation stations of inner and outer Tianshan area during 1992~2005, the velocity field of contemporary crustal deformation in Tianshan area is calculated and the characteristics and means of crustal movement in Tianshan area are analyzed quantitatively. The deformation of this area is controlled by boundary faults. From west to east, the velocity of convergence decreases, the velocity of west Tianshan (72°~77°E) is (20±1)mm/a, the middle Tianshan (77°~82°E) (12±1)mm/a, and the east Tianshan ( 82°~92°E) only (4±1)mm/a. The average velocity of convergence of whole Tianshan is 12mm/a.However the shortening of the crust in Tianshan area is not uniform:The main deformation takes place at the reverse fault and fold zone along both side of Tianshan Mountain. At the inner of Tianshan, the velocity of convergence is nearly zero, i.e. it looks like a rigid body. At the same time, the deformation intensity of the whole Tianshan has a good consistency with the seismic activity. The differential movement of lithosphere and asthenosphere causes the Neozoic deformation of Tianshan. The difference between the crust shortening rates in west and east direction of Tianshan, is resulted from the pushing action by Pamir and the clockwise rotation of Tarim. In the west Tianshan (west to 75°E), the convergence is caused by the push of Pamir in NNW direction, and in the east to 75°E, the difference of tectonic deformation is caused by the clockwise rotation of Tarim.
Niu Zhijun,You Xinzhao ,and Yang Shaomin . ANALYSIS OF CONTEMPORARY CRUSTAL DEFORMATIONCHARACTERISTICS WITH GPS DATA OF TIANSHAN MOUNTAIN[J]. , 2007, 27(2): 1-9.
Niu Zhijun,You Xinzhao ,and Yang Shaomin . ANALYSIS OF CONTEMPORARY CRUSTAL DEFORMATIONCHARACTERISTICS WITH GPS DATA OF TIANSHAN MOUNTAIN[J]. jgg, 2007, 27(2): 1-9.
