Recent progress on the research of Re–Os geochronology and Re–Os elemental and isotopic systematics in petroleum systems

Abstract

Re–Os geochronometer has been used in the dating of generation-accumulation, thermal cracking, and thermochemical sulfate reduction of crude oil and the oil-source correlation of petroleum systems in recent years. Re and Os concentrations are higher in the asphaltene fraction of crude oil and the earlier precipitated fractions of asphaltene. The correlations of the Re–Os isotopic systematics between asphaltene and maltene and among the fractions of asphaltenes are complex. It is shown by experiments that Re and Os can transfer from water to oil rapidly in a significant amount. However, Re–Os dating with multiple crude oil samples is suffering from great uncertainties while single oil dating methodology does not always work. A bright future for the application of Re–Os geochronometer on the dating of crude oil generation and accumulation requests further research on the homogenization mechanism of 187Os/188Os, the closed system of Re–Os systematics, and how Re and Os reside in crude oil.