论文部分内容阅读
最近对跨越南加州圣安德烈斯断层系的大地测量点位的速度进行了分析,分析结果揭示出震间形变沿12条剪切应变率较高的近乎平行的狭窄带发生。这些高剪切应变带与活动地质断层段对应很好,与微震活动集中带局部对应。从圣安德烈斯断层大弯处向北和向南都观测到了较高的剪切应变率(0.3～0.95微应变/a),而大弯处本身则表现出分散且量级低的剪切应变率。扩散性形变分散且量级较低(<0.2微应变/a),压缩性形变在文图拉和洛杉矶盆地最高。由于以前在该地区从未作过地质、构造和地震活动的假设,因此,我们的分析可以证明大地测量可单独用来探测活动断层段。
Recent analyzes of the geodetic velocities across the San Andrés Fault System in Southern California reveal that the onset of inter-seismic deformations occurs along nearly parallel narrow bands of 12 shear strain rates. These high-shear strain zones correspond well with the active geological fault segments, corresponding locally to the microseismic activity zone. Higher shear strain rates (0.3-0.95 microdissections / a) were observed both north and south from the large bends of the San Andrras fault, whereas the large bends themselves exhibited dispersed and low-magnitude shear Strain rate. Diffusion Deformation is dispersed with lower magnitude (<0.2 microstrain / a) and compressive deformation is highest in Ventura and Los Angeles basins. Due to the assumption that geology, tectonics and seismicity have never been done before in the area, our analysis proves that geodesy can be used solely to detect active fault segments.