东海陆架盆地丽水—椒江凹陷月桂峰组烃源岩特征及生排烃史

CHARACTERISTICS AND HYDROCARBON GENERATION-EXPULSION HISTORY OF YUEGUIFENG FORMATION SOURCE ROCK IN LISHUI-JIAOJIANG DEPRESSION,EAST CHINA SEA SHELF BASIN

丽水—椒江凹陷是东海陆架盆地油气勘探的一个重要领域,目前处于较低的油气勘探阶段。基于现有地质资料,在烃源岩发育特征及有机质丰度、类型和成熟度分析的基础上,采用含油气盆地数值模拟技术,定量恢复了研究区月桂峰组烃源岩的生排烃史。结果表明,月桂峰组烃源岩有机质丰度高,有机质类型以Ⅱ1型和Ⅱ2型为主,具有油气兼生的能力,总体上处于成熟阶段和高成熟阶段;月桂峰组烃源岩具有较高的生排烃强度,总体上经历了2次生排烃过程,但在不同构造单元存在明显的差异性。总之,以月桂峰组烃源岩为油气来源的含油气系统是该区油气勘探的主要目标。

The Lishui-Jiaojiang Depression is an important petroleum exploration target in the East Chi- na Sea Basin,which remains in the early stage of petroleum exploration. In this paper, geological data and the abundance,type and maturity of organic matter of the Yueguifeng source rocks were analyzed. Based on the data, hydrocarbon generation and expulsion history is quantitatively reconstructed. The results show that the abundance of organic matter is rather high in the Yueguifeng source rock, the organic matter is mainly belonging to types Ⅱ1 and Ⅱ 2, and the source rock are matured and highly matured. It means that the Yueguifeng source rock has the ability to generate both oil and gas. The Yueguifeng source rocks have passed two times of hydrocarbon generation and expulsion. However, the history varies in different tectonic unit. In a word, the petroleum system in Yueguifeng Formation should be the major exploration target in the study area.