中国海相盆地油气资源动态评价与有利勘探方向

Marine basins in China:Petroleum resource dynamic evolution and exploration directions

中国海相盆地是油气大突破的重要领域。立足中国含油气盆地分析,通过全球超大陆旋回,认为元古代以来3个克拉通海相盆地总体经历了4个地史阶段,明确了海相层系原型盆地演化序列与并列迭加特点,总结梳理了3类原型4种控源模式,表明原型盆地决定了烃源岩发育的环境及分布模式,编制了三大盆地主要层系分类型烃源岩分布图,并明确了烃源岩特征;基于海相烃源岩生烃—排烃—滞留油气动态演化模式,建立了海相层系烃源岩有效性动态评价和“常规—非常规”一体化资源评价等方法技术体系。基于新方法计算了海相层系生排烃量和资源量,明晰了重点盆地油气资源潜力分布。提出了大于10亿t资源量区带15个、5~10亿t级区带13个,指出了下步海相层系勘探的重点领域和方向。

Marine basin exploration is an important breakthrough in China's quest for oil and gas resources.Based on the analysis of China's petroliferous basins and theory of supercontinent cycle,we consider the three cratonic marine basins in China have in general experienced four evolutionary cycles since the Proterozoic.In this paper,the stratigraphic sequence and the juxtaposition-superposition characteristics of the marine prototype basins are clarified,and the three types of prototype basins and four source-control modes are summarized to show the prototype-basin control on the petroleum source-rock environment and distribution modes.In addition,the distribution maps of the main strata and source-rock types in the three basins are compiled,and the source-rock characteristics are defined.Based on the dynamic evolution model of hydrocarbon generation-expulsion-retention in the marine source rocks,the methodologies for dynamic evaluation of source-rock effectiveness and combined“conventional and unconventional”resource evaluation are established.Based on the new methodology,the hydrocarbon generation-expulsion volume and resource volume of marine strata are calculated,and the distribution of potential petroleum resources in key basins is clarified.The paper proposes 15 resource zones with more than 1 billion-ton(in total)and 13 zones with 0.5-1 billion-ton(in total)petroleum reserves,and points out the next key areas and directions of marine strata exploration.