【摘要】 本文根据地球物理、地震学资料及区域构造应力场的分布，研究了１９９０年４月２６日发生了７．０级地震的共和盆地邻近地区的隐伏构造。本文提出，在微观上该地震由沿震源区存在的东西向断裂的左旋剪切运动所引起，在宏观上则由区域性东西向构造的端部破裂所产生。同时，研究结果也表明深部发震构造并不与地表构造特征一致。主题词：更多还原

【Abstract】 In this paper, With geophysical and seismological data as well as the regional tectonic stress distribution,the subsurface tectonics in the vicinity of the Ms 7.0 earthquake occurred in Gonghe Basin on April 26,1990 has been studied. It has been proposed in this paper that the event was caused, in microscopic view,by the left-lateral shear motion along the EW trending fault in the focal zone and, in macroscopic view,by the extreme rupture along the regional EW trending tectonics. In the same time, the study result has also shown that the tectonic feature in surface did not coincide with that in subsurface.更多还原