Research Status and Progress of Genetic Mechanism of Abnormal Regular Sterane Distribution in Geological Bodies

Abstract

Regular steranes occur ubiquitously in petroleum and hydrocarbon source rocks as an important composition part of biological markers. Abnormal regular sterane distribution occurring in hydrocarbon source rocks and crude oils has been widely reported in recent years, but their origin and genetic mechanism are unclear. This research gives an overview of regular steranes in sediments and crude oils, and states its possible development directions in the future. Based on systematic research on compound-specific carbon isotope compositions of regular steranes in sediments and crude oils using separation, enrichment, and purification of regular steranes in sediments and crude oils, combined with organic petrological, micropaleontological, and sedimentary geochemical characteristics of hydrocarbon source rocks with abnormal distribution of regular steranes, the occurrence, variation and main controlling factors of these compounds will be discussed, thus further uncovering their genetic mechanism and probing into their application on assessment of organic matter source, depositional environment and thermal maturity, as well as oil and source correlation. It not only enriches and improves the approaches and theories on biomarker study, but also will be the breakthrough for the new theory and application in oil and gas exploration.