tectonic active area造句

• The analysis of structural movement and expression shows that qinqi tectonic active area is a volcano - sendimentary compressional depression formed by several times of compression movement from lower proterozoic , and spreaded in the direction of north step by step till the forming of xiangshan and miboshan group in mid - later period of ordovician , bearing hardly with volcanical rock
  从秦祁构造活动带的构造形迹分析认为，该构造带是自下元古以来多期挤压环境下形成的火山一沉积压陷，并一期又一期向北蚕食，于奥陶纪中后期形成基本不含火山岩的米钵山组、香山群压陷岩系。