Analyzed methods and progress of petroleum accumulation timing

Traditional methods for petroleum accumulation timing are based on research of structural history, trap evolution, and hydrocarbon generation and expulsion and analysis of oil generation for source rocks, timing of trap formation, and reservoir saturation pressure, which is indirect methods. Recently, with development of geochemistry and organic petrology, various methods based on fossil records are applied in research of timing of petroleum, which provided many measures including: reservoir diagenesis and hydrocarbon fluids emplacement events,authi-genic mineral isotope geochronology, fluid inclusions,reservoir magnetic mineral paleo magnetism, and accurate analysis of hydrocarbon generation history. This paper also discussed the actual application and existing problem of these methods.