中国海相层系油气成藏年代学

The Geochronology of Petroleum Accumulation of China Marine Sequence

我国海相叠合盆地存在多期构造运动、多期生排烃、多期成藏以及后期调整改造等特点,使得确定油气成烃成藏年代极其困难,因此基于我国典型海相复杂油气藏的成藏理论和油气资源勘探开发需求,综述了近年来有关海相层系油气藏成藏年代学的研究,重点介绍了流体包裹体分析、稀有气体氦氩同位素方法、矿物(U—Th)/He定年分析和自生伊利石K(Ar)—Ar定年等成藏定年的基础和研究进展,并对每种定年手段的优缺点以及适用范围进行了评述,最后提出在对我国海相层系油气成藏年代研究时,不能单凭某一种定年方法来判断,而应综合利用不同定年技术方法,同时要结合传统地质学分析方法来综合判断油气充注与成藏时间的思路,希翼推动海相油气成藏定年的发展,并为海相油气成藏理论的深化完善拓展研究思路。

The superimposed basins underwent multistage tectonic activities, hydrocarbon generation and expulsion, accumulation, and subsequent transformation in China. The multi-cycle evolution of basin hampers the study of geochronology of hydrocarbon accumulation. In order to solve this problem, we summarized the research progress of geochronology of hydrocarbon accumulation, and emphatically introduces the fundament of hydrocarbon accumulation dating methods,such as the analyses of fluid inclusion,the He and Ar isotopes of noble gas,the （U--Th）/He dating of apatite and zircon,and the K（Ar）--Ar dating of authigenic illite. Based on the merits and disadvantages of all the methods, we think it is difficult to obtain hydrocarbon accumulation age through one single method, integrate dating combining geological analyses is necessary. Such thoughts could shed light on the geochronology of hydrocarbon accumulation of marine sequence, and offer helps for deepening the theory of petroleum entrapment of marine sequence.