渤海湾南部埕岛地区中生代变形特征及构造演化

应用钻井资料、地震资料并结合区域资料，对渤海湾南部埕岛地区的中生代构造特征及演化进行了研究。研究表明：埕岛地区三叠纪以挤压变形为特征，变形的构造线方向为北西一北北西向，发育了北西向背斜和北北西向逆断层，埕北20断层在此时期是典型的逆冲断层；晚侏罗世一早白垩世以伸展变形为特征，发育了受北北西向断层控制的断陷，在断陷内发育了巨厚的中生界，埕北20断层此时为研究区主要正断层，同时还受走滑作用的影响，近东西向右行走滑断层错断了北北西向的埕北20断层；晚白垩世受挤压应力的影响发生变形，早期正断层发生正反转，断层上盘发育了与断层形态有关的褶皱。图8参8

Mesozoic deformation and tectonic evolution in Chengdao, Southern Bohai Bay

The paper applies seismic and well-log data to the study of the Mesozoic structural characteristics and tectonic evolution in Chengdao Region. In Triassic, the NW-trending folds and NNW-trending reverse faults developed in Chengdao Region as a result of compressive stress, and the Chengbei 20 fault was a representative reverse fault. From 1.ate Jurassic to Early Cretaceous, the structural characteristic was mainly extension in the region, and there developed fault basins controlled by NNW-trending normal fault. The Chengbei 20 fault, which controlled the very thick Mesozoic deposits, was the chief basin-controlled fault in Chengdao Region at the stage. Simultaneously, EW-trending dextral strike-slip faults cut Chengbei 20 fault. Because of contracting deformation, the unconformity between Cenozoic and Mesozoic and inversion structures were formed in Late Cretaceous.