摘要：

辽河西部凹陷油气资源非常丰富，通过对己勘探发现的773个油气藏的地质特征参数统计认为，西部凹陷油气藏类型非常丰富，但主要以构造和岩性油气藏为主，且复合油气藏发育，统计表明，近90%的油气藏与断裂有关。油气藏类型受构造带控制作用明显，缓坡带最要以背斜、岩性构造油气藏为主，中央背斜带背斜断块油气藏较为发育，而陡坡带则多为岩性油气藏。沉积相带控油气作用明显，油气藏主要分布在扇三角洲、三角洲和浊积扇相。油气资源在空间上遵循“油气总量平衡模式”，无论在平面上还是层位上，油气资源互补特征性强。研究认为西部凹陷具有生烃洼陷、断裂、异常压力、沉积相带联合控藏的特点。首先沙三段、沙四段有效烃源岩大量发育，资源量极为丰富，为西部凹陷油气富集提供了物质保证，油气藏分布主要受生烃洼陷控制；各组段砂体叠合连片，平面展布连续，具较好的储集能力，也为油气的侧向运移提供的条件；另外东营末期因走滑引起的大量泄压断裂发育，为油气大规模远距离垂向运移提供了可能。

Abstract:

There is abundant Oil and gas in the western sag. According to the statistical analysis of the geological factors of 773 reservoirs discovered, it is considered that there are various reservoir types in the sag, with structural and lithological reservoirs dominating and composite reservoirs developing. The statistics data show that nearly 90% of reservoirs are related to faults. The types of reservoir are significantly controlled by structural belt. There are mainly anticlinal and lithological-structural reservoirs in gentle belt, anticlinal and fault block reservoirs in central anticlinal belt, and lithological reservoirs in steep slope belt. Reservoirs are obviously controlled by sedimentary facies, and mainly distribute in fan delta facies, delta facies and turbidite fan facies. The spatial distribution of oil and gas resources follows “the model of the total oil and gas resources balance”, and shows obvious complementary characteristic on both the plane and the stratigraphic horizon. According to research, the distribution of reservoirs is jointly controlled by hydrocarbon generation sag, faults, abnormal pressure and facies in the western sag. Firstly, the active source rock in Sha 3 Member and Sha 4 Member are well development and the resource quantity is very large. So they form the base of hydrocarbon enrichment and control the distribution of reservoirs in Western Sag; Secondly, oil-bearing sand bodies of each Formation and Member are overlapped and continuous plane distribution, which is favorable to lateral migration; Thirdly, the development of pressure relief faults led by the strike-slipping at the end of Dongying phase, which makes the oil and gas large scale and far-distance vertical migration possible.