莱州湾西构造带断裂特征及其对油气成藏的控制

Characteristics of faults and their control to hydrocarbon accumulation in the western tectonic zone of Laizhou Bay Sag

受古近纪莱州湾凹陷大规模断陷、郯庐断裂右旋走滑和垦东凸起大规模隆升三方面因素共同作用,莱州湾西构造带断裂系统发育,根据断裂性质及发育规模将断裂划分为3组不同方向的断裂组合,对油气的运移、聚集及保存都产生重要影响。根据莱州湾地区油气成藏规律并结合渤海其他区域近年勘探成果综合分析,莱北1号断层、斜坡区东西向反向正断层和走滑末端雁行式断层三类大规模调节断层对于油气成藏影响作用较大,这三类断层所控制的圈闭也是莱州湾凹陷及围区下一步勘探获得突破的重点区域。

Faults were well developed in the western tectonic zone of Laizhou Bay Sag affected by rift of Laizhou Bay Sag in Peleogene period, Tanlu dextral strike-slip fault and large scale rise of Kendong uplift. Two kind of faults including strike-slip fault and extensional faults are identified based on faults nature and developed scale, which affected hydrocarbon migration, accumulation and preservation. Based on hydrocarbon accumulation in Laizhou Bay area and exploration result in other area of Bohai Sea, 3 kind of faults make a good effect to hydrocarbon accumulation in the western tectonic zone including Laibei No. 1, reverse normal fault with E-W trending in slope area and echelon faults in the distal end of strike-slip fault. The traps controlled by these 3 kind of faults are the favorable regions in Laizhou Bay Sag and its surrounding areas.