摘要
在对四川盆地及其西部边缘震区航磁资料进行分析研究的基础上,依据频率域磁性单界面反演方法对航磁异常进行了数据处理,求取了基底磁性界面的定量埋深,结合区域构造特征、地热分布及板块运动对地震的孕育环境进行了综合研究和讨论。在前人的研究基础上,明确提出四川盆地西部边缘地区的地震活动是在青藏高原东部的川青块体向南东方向滑移,川滇菱形块体向南南东方向沿移,与扬子板块的俯冲构造相碰撞产生的板块二级构造应力场的作用下孕育和发生的。
on the basis of analysing aeromagnetic data from Sichuan basin and its western marginal seismic area,aeromagnetic anomaly data processing is processed in terms of myer sion method for frequency domain single magnetic interface, and the quantitative buried depth of basement magnetic interface is obtained. Seismogenic environment is studied and discussed comprehensively in the light of regional tectonic characteristics, geothermaldistribution and plate motion. Based on predecessors' studies, we conclude that earthquakes in tile western marginal area of Sichuan basin is developed and occurred under the action of second - order plate tectonic stress field, which resulted from collision of Sichuan Qinghai block in the east of Qinghai- Xizang plateau gliding towars SE, Sichuan- Yunnanrhombic block gliding towards SSE, with the underthrust tectonics of Yangtze plate block.