下扬子区海相中、古生界上油气成藏组合特征分析

Analysis of characteristics of upper hydrocarbon play of Mesozoic-Paleozoic marine group, Lower Yangtze region

徐曦 杨风丽 赵文芳

XU Xi YANG Fengli ZHAO Wenfang

同济大学海洋与地球科学学院, 上海 200092; 中国科学院油气资源研究重点实验室, 北京 100029

State Key Laboratory of Marine Geology, Tongji University, Shanghai 200092, China; Key Laboratory of Petroleum Resource Research Institute of Geology and Geophysics, Chinese Academy of Science, Beijing 100029, China

下扬子地区海相上组合(主要为中生界、上古生界)经历了印支运动、燕山运动、喜马拉雅运动的叠加改造,生、储、盖油气成藏诸要素被改造调整,海相中、古生界油气成藏条件复杂。基于海相上油气组合的成藏演化过程与时空匹配的分析,可以认为上油气成藏组合具有良好的生、储、盖配置关系;三次油气的关键充注期后,基本没有经历大的油气破坏和改造作用;成藏要素在时空上有效配置,将是下扬子地区最有油气勘探前景的海相油气成藏组合。沿江地区,处于南北对冲前缘带,是海相地层的弱变形区,地层保存相对完整,成藏配置较好,发育"古生新储"、"古生古储"的油气藏,为下扬子地区最有利的勘探区域。

With multiple stages of tectonic evolution in the Lower Yangzte region, the upper hydrocarbon play (mainly in the upper Pa-leozoic and Mesozoic) has been strongly superimposed. The source rock, reservoir, cap are adjusted and reconstructed, which results in the complex conditions of petroleum accumulation. Based on the analysis of the process of petroleum accumulation and time-space matching relation, this paper indicates that the source rock, reservoir rock and cap rock of the upper hydrocarbon play have an excel-lent combination. Essentially, the play has not been destroyed and reformed strongly by the later tectonic movements. And the reservoir forming factors are valid in time and space. It is the most prospective play in the Lower Yangzte region. Meanwhile, the hydrocarbon play is the essential condition of late entrapment. Yanjiang area, located in south-north hedge frontal belt, is the weak deformation zone of marine strata in which the strata is relatively complete and the reservoir forming factors have been deposited well. The hydrocarbon reservoirs of Paleozoic source-Cenozoic reservoir and Paleozoic source-Paleozoic reservoir are found in this area which is the most fa-vorable exploration areas in Lower Yangzte region.

中石化股份有限公司海相基础前瞻性研究课题子课题"下扬子中、古生代海相盆地形成演化及油气潜力分析"资助(No:YPH08035)。

https://doi.org/10.3969/j.issn.1008-2336.2011.04.048