湖北省随枣地区推覆构造格局及其演化

NAPPE STRUCTURAL FRAMEWORK AND TECTONIC EVOLUTION OF SUIZHOU AREA OF HUBAI PROVINCE

上地壳多层次自北而南逆冲-拆离是本区构造格局的基本特征。区内柳林、洪清、大洪山三条逆掩断层与深部拆离面一起构成了一尖端指向南的楔形薄皮构造。逆掩断层最大位移量可达107km,逆冲系统以背驮式扩展演化。多层次推覆构造格局因后期高角度断裂的切割破坏而复杂化。构造格局的定型时代为燕山期。

The area studied is characterized by the southward polyleveled thrusting and decoupling in the upper crust. Evidences show that thin-skinned tectonic wedge, decreasing toward south in thickness, is constituted by the Liulin, Hongqing, Dahongshan thrusts and deeplevel decoupling in this area. It is estimated that the displacement of the Liulin sheets is 107 km or so. The thrust system propagated in a piggy-back fashion. This area exhibits a com- pllenied thrusting framework, as it is cut by several high-angle faults extending parallel to the mountain building belt. The finalized period of tectonic framework is the Yanshanian period.