摘要： 辽东湾北部地区右行走滑构造特征较为典型,主要表现为:沿走滑断裂带发育雁行式伸展断裂; 剖面上发育花状构造;走滑断裂沿走向呈“S”型或反“S”型波状弯曲;沿走滑断裂带断槽与断鼻构造相间分布。分析认为,渐新世晚期,辽东湾北部地区南北向拉张、东西向挤压的区域应力场控制了右行走滑构造的形成,断槽与断鼻构造相间分布是由于沿走滑断裂带局部应力场性质发生改变所致。右行走滑断裂的“S”型弯曲部位为增压弯部位,走滑断裂两侧断块在此汇聚,地层因应力集中而形成断鼻构造;右行走滑断裂的反“S”型弯曲部位为释拉张部位,走滑断裂两侧断块在此离散,地层因拉张而发生断陷形成断槽。受走滑构造所控制,油气沿走滑断层自断槽向断鼻方向运移、聚集而成藏。研究走滑构造发育特征,对于预测圈闭分布以和研究油气富集规律具有重要意义。

关键词: 辽东湾, 走滑构造, 断鼻, 断槽, 构造分析, 油气富集规律

Abstract: The dextral strike-slip structure styles were typically developed in the northern Liaodong Bay. The characteristics are as follows: echelon faults are developed along the strike-slip fault zone, flower structures can be seen in the sections, strike-slip faults are distributed as S-shape and fault troughs and fault noses are alternately distributed along the strike-slip fault zone. Studies show that the dextral strike-slip structures were controlled by the stress field of south north extension and west east compression in which the fault troughs and the fault noses were alternatively distributed due to the changes of the local stress field along the strike-slip fault zone. The stress concentration and the strata compression occurred at the S-shaped constraining bends, while the stress relaxation and strata extension happened at the anti-S-shaped releasing bends. Therefore, the fault noses are generally formed near the constraining bends while the fault troughs near the releasing bands of strike slip structures. Hydrocarbon migrated from fault troughs to fault noses and petroleum were finally accumulated along the constraining bends. It is significant to study the characters of the strike-slip structures for trap prediction and prediction of rules of hydrocarbon accumulation along the strike-slip fault zone.

Key words: Liaodong Bay, strike-slip structure, fault nose, fault trough, structure analysis, rule of hydrocarbon accumulation

中图分类号: 

• P542.2