北大港构造带东翼断层的封闭性

参考了构造应力场模拟成果,对北大港构造带东翼所有断裂在华北运动期、喜马拉雅运动期、新构造运动期的封闭性进行测算统计、定量分析。结果表明,分布比较有限的近东西向或南东东—北西西向断裂,在华北运动期开启性最好,最有利于油气运移;分布最广的北东东向断层在华北运动期具有较好的开启性,是油气运移的良好通道,在新构造运动期,这些断层张裂更明显,可促使油气进一步上升,甚至流出地表;北北东向断层在华北运动期封闭性较好,在喜马拉雅运动期开启性较好,有利于油气的运移,在新构造运动期再次为比较封闭的状态,可能成为油气藏形成、保存的有利条件;在新构造运动期新生的北东东向断层,活动性较强,张裂较明显,成为油气运移的良好通道。

Fault Sealing in East of Beidagang Tectonic Belt

The fault sealing performance of all faults in Paleocene tectonic period,Himalayan tectonic period,Neocene tectonic period in the east of Beidagang tectonic belt was measured and calculated and quantitatively analyzed,by means of the results of tectonic stress field simulation.The results show that distribution-limited faults near EW or SEE-NWW trending were best opened in Paleocene tectonic period in this studied area,and the most beneficial to oil and gas migration and accumulation.The most widely distributed NEE trending faults were better opened in this period and could be as good parts for oil and gas migration and accumulation.In Neocene tectonic period,these faults were also the most obviously splayed,allowing oil and gas to rise further and even outflow from the surface.NNE trending faults were closed better in Paleocene tectonic period and opened better in Himalayan tectonic period,favorable for oil and gas migration and accumulation,but appeared in relatively closed state again in Neocene tectonic period,which were probably favorable conditions of reservoirs formation and preservation.The NEE trending faults newly generated in Neocene tectonic period were characterized by stronger activity and apparent tension cracking,which may become good channels for oil and gas migration.