Study on microbial carbonate formation and hydrocarbon deposition

Abstract

Microbial carbonate rocks are mainly developed in older strata and are often buried deep. Deep oil and gas exploration has great potential because of its potential source rocks, reservoirs, and abundant oil and gas resources. Through the classification of microbial rock types, it is of great significance to study microbial carbonates deposited in geological history in petroleum exploration. First, microbial carbonates can be used as a good indicator of paleoenvironment and Paleoclimate, which is conducive to paleogeographic reconstruction; Second, the type of organic matter can be evaluated by analyzing the characteristics of biomarkers of microbial carbonate deposits; third, the hydrocarbon-generating capacity can be evaluated by studying the preservation of organic matter in microbial carbonates. Based on the analysis of the development conditions of microbial carbonate and the oil-gas accumulation model, it is considered that the microbial carbonate formation and pure microbial carbonate formation developed in the slope sedimentary environment can not only become an oil-gas reservoir but also serve as one of the oil-gas generating reservoirs. Among them, the formation dominated by biological reefs and supplemented by microbial carbonate is close to the marine source rock formation or directly covered by marine oil shale. Under the transgressive system, it is easy to form a good cap rock, which has a good reservoir-forming potential.