Abstract: On the base of detailed research on marine source rocks in China by means of organic petrology and geochemistry, a new maceral-marine vitrinite has been confirmed.This maceral origins from faunal organic matter, were formed through the strong biochemical degradation of bacterials under the reducing to strong reducing conditions.Thermal-simulating test results showing that marine vitrinite is characterized by late hydrocarbon generation, and its oil peak occurs in the region of vitrinite R_o 1.0%~1.30%.Marine vitrinite is a good gas source material although its liquid hydrocarbon production is about 6%~8% of its total weight.The reflectance of marine vitrinite can be used as a good maturation level index after high maturation level stage.

Key words: marine vitrinite, source rocks, hydrocarbon generation

摘要： 应用现代有机岩石学与有机地球化学相结合的方法,通过对我国海相烃源岩的研究,确认了一种新的显微组分--海相镜质体。这种显微组分源于动物有机质,在还原-强还原条件下,经强烈生物降解作用形成。人工热模拟实验表明,海相镜质体成烃较晚,主成油期在镜质组R_r1.0%～1.30%范围内,产油率高达6%～8%,并以气态烃为主。海相镜质体反射率在高成熟阶段后可作为良好的成熟度作用指标。

关键词: 海相镜质体, 源岩, 成烃作用