Abstract:

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.

Key words: deep marine strata, basin prototype controls provenance, resource potential, dynamic evaluation, new field