东营凹陷东辛油田油源分析和成藏过程研究

Oil source correlation and oil accumulaion process of the Dongxin oilfield, Dongying depression, China

东辛油田是东营凹陷中央背斜带复式含油气聚集带的一部分,是一个多油源汇集的地区,油源关系复杂。根据地球化学和石油地质综合研究,对其油气来源和成藏过程进行了分析。根据油源和构造特征,东辛油田大致可划分为三个区辛镇构造区,为低成熟-成熟的沙四型原油;东营构造区,以沙四型成熟原油为主;东营构造以西区,主要为沙三型成熟原油。结合地质分析认为,东营构造区至少存在两期重要的成藏过程,而辛镇构造和东营构造以西区仅存在明化镇期至第四纪一期成藏过程。该研究对于东辛油田今后的隐蔽油气藏勘探具有重要的意义。

The Dongxin oilfield is a part of the oil and gas accumulating zone in the central anticline of the Dongying depression and has very complex oil source relations. Oil and gas source correlation and oil accumulation process are studied through the integrated geochemistry and petroleum geology study. According to the oil source and tectonic characteristics, the oilfield can be divided into three blocks. The Xinzhen structure is predominated by low mature to mature oils originated from E_~2-3 s_4~u , the Dongying structure is dominated by mature oils originated from E_~2-3 s_4~u , while the west part of the Dongying structure is predominated by mature oils originated from E_~2- . Combined with the comprehensive geology analysis, the author suggests at least two oil accumulation stages happened in Dongying structure, while there is only the late stage in the Xinzhen structure and the west part of Dongying structure. The study has great significance in future exploration of the Dongxin oilfield.