下扬子区构造变形特征与页岩气保存条件

通过大量野外地质踏勘资料与室内钻井及地球物理资料分析剖析了下扬子区的区域构造变形特征及其页岩气保存潜力。结果表明：下扬子地区中新生代的构造运动在不同地区表现为不同的样式，不仅表现为南北分为根带、中带、锋带的特点，其东西方向上的差异也十分显著；东部地区的构造样式主要受到志留系滑脱层的控制，主要表现为侏罗山式褶皱构造，主要保存了印支期和燕山期的构造样式，后期拉张和构造反转对其影响相对较弱，页岩气保存条件较好；而茅山以西地区受到了后期拉张与构造反转的强烈改造，并形成了一系列的拉张断陷盆地和火山盆地；这种构造特点使得此区域勘探难度大，页岩气保存条件差。

Structural deformation characteristics and shale gas preservation of Lower Yangtze region

Based on the analysis of field observation，drilling data and geophysical data，this paper interpreted the structural deformation characteristics of Lower Yangtze region and its preservation potential for shale gas.The results show that the deformation characteristics of Lower Yangtze region vary in different areas.The structural style is not only different from south to north，but also from east to west.To the east of Maoshan，the structure style is mainly controlled by decollement folding，which was caused by the Indosinian-Yanshan movement.The following extension and reversion movements greatly are destroyed the previous structures.So it still has good shale gas preservation conditions for shale gas and not very hard to explore.The west Maoshan region，however，is strongly reworked by strong reverse and tension movements since the Indosian-Yanshan movement，and as a result a serious of extensional and faulted basins and volcanic basins were formed，which are very negative for the shale gas preservation and explorations.