A Study To Character Of China Mainland Strain Field By Using GPS Data From CMONOC

China Mainland, which in the southeast corner of the Eurasian Plate, surroundedby the Pacific-Indian and Eurasian plate body, its unique structural conditions of intracontinental deformation and block makes the interaction and structural phenomenavery complicated, is the most intense tectonic movement areas in the world. Aquantitative description of tectonic kinematics is a prerequisite for qualitativeunderstanding of physical properties of continental lithosphere and its dynamicaspects which control the continent deformation, which are of critical to revealearthquake mechanism and forecast earthquake.Global Positioning System (GPS) measurement, with its outstanding merits suchas high precision, low expense, dense distribution and flexible has become one of theprimary means of studying crustal movement. GPS which has produced rich results inplate tectonics, the Earth’s rotation, seismic monitoring and other aspects demonstratebroad application prospects. With tectonic deformation and geodynamics in the Asiacontinent, GPS can play a unique role, and will be undergoing profound changes.From1990s, the GPS data have been accumulating progressively in China. As yet, aunified measurement of crustal deformation velocity field for the Chinese Mainlandhas been available, based on the sophisticated analysis of these data. So thisdissertation makes research on stress and strain field analysis and tectonic activity inChina Mainland with CMONOC velocity field from2009to2011on the basis ofreferring to much1itemture information.This dissertation firstly introduces China mainland active tectonic features andits driving mechanism basis on Deng’s District of active tectonics. Studies shown thatthe basic characteristics of the China mainland have huge difference bounded to thenorth and south active tectonics belt, west crustal deformation performances extrusionproperties and tensile for east, the main faults in the Quaternary slip rate between1to20mm/a, while the eastern range of less than1mm/a, significantly weaker than thewest. China crustal movement velocity field shows that the crustal thickeninghypothesis may more realistically reflect the dynamics of continental tectonicdeformation mechanism. Secondly, systemically expounds research method of horizontal crustaldeformation, mainly analysis the velocity field characteristics of China mainland onthe basis of domestic and foreign scholars research on the Chinese mainland. Theresults showed that the Chinese mainland west movement rate was significantlygreater than the eastern, western horizontal crustal movement rate is generally10~30mm/a, the east is less than10mm/a, crustal movement has a very obvious "weststrong and east weak" characteristic, this corresponding to geological results and thevalue slightly larger. Another obvious feature is that the characteristics of the crustalvelocity with a clockwise rotation around the eastern Himalayan syntaxis.Finally, we systemically analysis the strain rate field characteristics of fourregions (Sichuan-Yunnan, Tibet, Tianshan and North China) that have Significantlydeformation in china mainland. The results showed that the strain value of the Chinamainland as a whole is10-8/a, the high value areas are more concentrated in activeplate at the junction of the fault zone and its nearby areas. Present-day crustaldeformation and earthquake activity relationship analysis showed that the active blockmutual intersection is often the crust deformation mutation, is also a high incidence ofearthquake activity.