黄骅坳陷新生代断裂构造系统研究

Faulted structure systems of Huanghua Depression in Cenozoic era

黄骅坳陷断裂构造极为发育,其新生代构造系统主要为伸展构造系统,以铲形正断层或坡坪式正断层为主干伸展断层,以不同尺度的北东—北东东向正断层和具调节性质的北西—北西西向断层为特征。经过对黄骅坳陷新生代构造应力场的分析,黄骅坳陷盖层中极难出现明确的走滑断裂,其雁列状排列的断层应为倾斜滑动断层;黄骅坳陷中不同凹陷或断块之间不同的伸展程度往往为横向地垒状凸起、鼻状凸起或鼻状背斜所调节,在横向凸起和凹陷之间伴生北西向正断层,它们与挤压变形体系中具有走滑性质的横向变换断层又有本质上的不同。

There are many faulted structures in Huanghua Depression,the extensional structural system is the main style of Cenozoic fault systems. The major extensional faults include listric normal faults or ramp - flat normal faults, which are characteristic of NE - NEE strike normal faults of different scale and NW -NWW strike adjusting faults. According to the analysis of regional structural stress field in Cenozoic,it's hard to form explicit strike - slip faults in Huanghua Depression, the faults with en echelon arrangement should be inclined dip - slip faults. The different extensional degree between different sags or faulted blocks is adjusted by transverse horst - shaped swell, nose - shaped swell or anticlines. The companion NW strike normal faults between lateral swells and sags are different constitutionally from lateral transfer faults in compression deformation system, which are strike - slip.