郯庐走滑断裂带消逝端断裂特征与油气成藏

Fracturing Features and Oil/gas Reservoir Forming at the Pinchout End of Tanlu Strike-slip Faulting Belt

郯庐断裂带发育郯庐走滑断裂,把渤南低凸起错断,并在渤中凹陷内消逝。走滑断裂分为上下2套断裂系统。走滑断裂平面上为雁列式排列的2支断裂,剖面上形成不同的构造样式。走滑断裂带控制了渤南低凸起北侧构造格局及油气成藏。断裂早期活动使该区形成2个古构造脊。古近系及其下部圈闭在古构造脊上继承发育,以断背斜类型为主;新近系圈闭分2类,郯庐断裂的晚期强烈活动促使了油气垂向运移及再分配,对晚期油气成藏有利。

Strike-slip fault developed in the Tanlu Faulting Belt breaks the Southern Bohai Low Bulge and pinches out in the central Bohai Sag. The fault is divided into 2 sets of faulting systems( upper and lower). In plane,it presents as 2 faulting zones in en echelon. In section,different structural patterns are observed. The strike-slip Faulting Belt controls structural patterns and oil/gas reservoir forming at the northern side of Southern Bohai Low Bulge. The faulting activities at the early stage led to the formation of two ancient structural ridges in the area. Paleocene and its underlying traps developed successively above ancient structural ridges,as mainly faulted anticline. Neocene traps can be divided into 2 types. The strong activities of Tanlu Fault Belt at the later stage promoted the vertical migration and redistribution of oil/gas,which was favorable for the oil/gas reservoir forming at the later stage.