On the basis of the velocity field results of horizontal crustal movement obtained from GPS measurements during the periods of 1993-1999, 1999-2001 and 2001-2003 in the northeastern margin of Qinghai-Xizang block, and...On the basis of the velocity field results of horizontal crustal movement obtained from GPS measurements during the periods of 1993-1999, 1999-2001 and 2001-2003 in the northeastern margin of Qinghai-Xizang block, and by the inversion of negative dislocation model for the elastic block boundaries, we provide in this paper a qualitative analysis and quantitative description for the difference of motion and deformation between the tectonic blocks and their boundary faults, time-space distribution of tectonic strain field, and locations with highly accumulated strain energy and correlative intensity. Furthermore, taking the regional tectonics and block strain into full consideration, we investigate the common features of background precursors relating to location prediction for M greater than or equal 6 earthquakes.展开更多
Using dislocation model of seismic deformation and the hybrid global inversion method, we analyze the 1990-1995 annually GPS data from 89 stations in southern Taiwan and its neighboring area and discuss the origin of ...Using dislocation model of seismic deformation and the hybrid global inversion method, we analyze the 1990-1995 annually GPS data from 89 stations in southern Taiwan and its neighboring area and discuss the origin of the observed deformation field. Based on the geologic investigation and seismic observation we simply assume six blocks and nineteen fault patches in the studied area. The results show that the Philippine Sea plate moves, relative to the Eurasian plate, at a velocity (69±2)mm/a in 317°±2°. About a half of the rate is concentrated on the Longitudinal Valley fault (LVF), and the other half of the convergence spread over the boundaries among the west blocks. The Philippine Sea plate and the Central Range move toward northwestward. In the west of the Central Range zone, the motion of the blocks accords with the observed fan-shape distribution of the maximum principal stress. The faults between the Western Foothills and the Coastal Plain geological provinces have main thrust components, and the dips turn small from south to north. The fault widths are about 10km, implying that they are strongly locked, and most of the large historical earthquakes occurred here.展开更多
基金Joint Seismological Science Foundation (603001)Project of China Earthquake Administration during the tenth five-year (100501-04).
文摘On the basis of the velocity field results of horizontal crustal movement obtained from GPS measurements during the periods of 1993-1999, 1999-2001 and 2001-2003 in the northeastern margin of Qinghai-Xizang block, and by the inversion of negative dislocation model for the elastic block boundaries, we provide in this paper a qualitative analysis and quantitative description for the difference of motion and deformation between the tectonic blocks and their boundary faults, time-space distribution of tectonic strain field, and locations with highly accumulated strain energy and correlative intensity. Furthermore, taking the regional tectonics and block strain into full consideration, we investigate the common features of background precursors relating to location prediction for M greater than or equal 6 earthquakes.
文摘Using dislocation model of seismic deformation and the hybrid global inversion method, we analyze the 1990-1995 annually GPS data from 89 stations in southern Taiwan and its neighboring area and discuss the origin of the observed deformation field. Based on the geologic investigation and seismic observation we simply assume six blocks and nineteen fault patches in the studied area. The results show that the Philippine Sea plate moves, relative to the Eurasian plate, at a velocity (69±2)mm/a in 317°±2°. About a half of the rate is concentrated on the Longitudinal Valley fault (LVF), and the other half of the convergence spread over the boundaries among the west blocks. The Philippine Sea plate and the Central Range move toward northwestward. In the west of the Central Range zone, the motion of the blocks accords with the observed fan-shape distribution of the maximum principal stress. The faults between the Western Foothills and the Coastal Plain geological provinces have main thrust components, and the dips turn small from south to north. The fault widths are about 10km, implying that they are strongly locked, and most of the large historical earthquakes occurred here.
