松辽盆地徐家围子断陷挤压变形特征

Characteristic of compression deformation of Xujiaweizi Rift in Songliao Basin

利用综合勘探程度较高的松辽盆地徐家围子断陷钻井与地震资料,对早白垩世早期(相当于热河生物群时代)的地层进行了构造特征研究。确定了徐家围子断陷是受徐西和宋西两条大断裂控制的复合断陷,控陷断裂NNW延伸的部位控制了宋站、杏山和肇州三个沉降中心的形成,沙河子组沉积末期和营一段火山岩喷发后的挤压作用在盆地内形成了断弯褶皱、断展褶皱和反转构造等构造样式,奠定了徐家围子断陷"二横三纵"的构造格局,控制了天然气的聚集。

This paper studies structural characteristics of early Cretaceous formation corresponding to Rehe biological group time, combining with drilling and seismic data of Xujiaweizi Rift in Songliao Basin with high exploration degree. It determines that Xujiaweizi Rift is a complex rift controlled by two large fractures, i. e. , Xuxi and Songxi fractures. Extension part of rift contro.lling fractures in NNW strike controls the formation of three subsidence centers of Songzhan, Xingshan and Zhaozhou. Compression action at the end of Shahezi Formation and after volcanic eruption in Ying 1 Member forms several structural styles including fault bending fold, fault extending fold and reversed structure. This constructs a structural framework of ＂two lateral and three longitudinal frameworks＂ in Xujiaweizi Rift, controlling gas accumulation.