四川棋盘格式构造是第四纪中更新世以来发展起来的最新构造型式,主要由北东、北西两组扭断裂组成。现今仍在继续发展过程中,是主要孕震构造——其中以北西向一组活动性最烈,是活动体系中最危险的活动构造。因此,只要抓住这一构造型式,就基本抓住了四川大部分地震活动的经络。 Sichuan chessboard format structure is the latest tectonic type developed since the mid-Pleistocene in the Quaternary, and is mainly composed of torsional faults in the north east and north west. Nowadays, the main seismogenic structures are still under development - one of the most active in the northwestern direction is the most dangerous tectonic activity in the activity system. Therefore, as long as this structural type is seized, the meridian of most of the seismic activities in Sichuan is basically captured.