Abstract:

〗Faults in study area are normal faults which are classified into four zones in plan. T₂ (Quantou formation top) and its underlying layers are clear in fault zonation, striking SN and to NW and to SN. Above T₂, fault zonation is poor due to a later reshaping from NE-and EW-striking faults. These faults display a rift-gabben developing mode. Faults are classified as four stages, of which medium and late faults are developed, closely connected to oil-gas migration and concentration. Inheritance faults play a role in migration in a middle- to long-term and in preservation in later stage. Faults control the formation of oil reservoir that oil is connected by faults through lateral migration. The oil-gas reservoir type is mainly faultlithology type with oil-gas concentration descending eastward, but ascending level in oil-bearing sequences.

Key words: fault features, faults stages, lateral migration, oil-gas reservoir

摘要：

研究区断层全部为正断层，平面上划分为4条断裂带。T2(泉头组顶面)层及其以下层位断裂条带性好，主要有南北向转北西向再转南北向的发育特点，T₂层以上由于北东向和近东西向晚期断层的加入使得断裂条带不明显。纵向上主要是堑垒相间的发育样式。研究认为本区共分为4期断裂，其中以中、晚期断裂最为发育，同时与油气运移与聚集关系最为紧密。中期和长期继承性断裂以运移作用为主而晚期断裂以保存作用为主。断裂对本区油藏形成具有明显的控制作用，石油被断裂沟通，以侧向运移为主，油藏类型主要为断层—岩性油藏，油气丰度由西向东逐渐递减且富油层位逐步抬升。

关键词: 断裂特征, 断裂期次, 侧向运移, 油气成藏 