埕岛地区古生界构造和地层多样性及形成机制

运用三维地震、钻井资料和区域应力场研究结果，探讨埕岛地区古生界构造和地层多样性的形成机制。结果表明，三叠纪末期-始新世，在郯庐断裂左旋→右旋"往返式"走滑运动控制下，埕岛地区古生界经历了"挤压倾伏褶皱、拉张反转成山、差异走滑定型"3个阶段。三叠纪末期，在郯庐断裂左旋走滑运动下，埕岛地区NE-SW向挤压、北西向倾伏褶皱，形成西、中、东3个逆掩断块体，差异隆升作用造成古生界剥蚀程度不一。晚侏罗世-早白垩世，在郯庐断裂左旋走滑运动下，埕岛地区经历NWW-SEE向→NW-SE向拉伸，逆冲断层发生不均衡反转形成西、中、东三排山和"南敛北散"形态。晚白垩世-始新世，在郯庐断裂右旋走滑运动下，埕岛3排山自西向东基底走滑剪切位移不断增大，中排山和东排山在基底剪切下发育的东西向断层和北东向走滑断层相互切割，构造样式和岩性分布更复杂。

The Formation Mechanism of Paleozoic Tectonic and Stratigraphic Diversity in Chengdao Area

In this study, we analyzed the formation mechanism of Paleozoic tectonic and stratigraphic diversity in Chengdao Area using 3D seismic, drilling data, and regional stress field results. The results show that affected by the left-lateral →rightlateral "reciprocating" strike-slip movement of Tanlu fault during the Late Triassic-Eocene period, Paleozoic in Chengdao Area experienced three stages including "compressing and plunging folds, stretching and reversing into mountains, and differential slipping and shaping". At the end of the Triassic period, the NE-SW region in Chengdao Area was compressed from SW to NE under the left-lateral strike-slip movement of Tanlu fault. This compression movement resulted in the formation of three overthrust blocks in the west, middle, and east. The difference effect in the uplift caused different degrees of erosion in Paleozoic. During the late Jurassic-early Cretaceous period, Chengdao Area experienced stretching from the NWW-SEE to the NW-SE direction under the left-lateral strike-slip movement of Tanlu fault. Unbalanced reversion of thrust faults forms three rows of mountains in the west, middle, and east, as well as the "convergence in the south and discrete in the north" fault. In the Late Cretaceous-Eocene, the base shearing displacement of the three rows of the mountains from the west to the east direction in Chengdao Area is increasing under the effect of right-lateral strike-slip movement of Tanlu fault. The EW fault and the NEtrending strike-slip fault formed due to the base shearing from the middle mountain and east mountain, respectively, which tend to cut into each other. The structural styles and lithology distributions are now more complex.