关键词: 干酪根碳同位素, 碳同位素组成, 原油, 液体烃, 热演化程度, 演化阶段, 热模拟实验, 成熟阶段, 变化关系, 油源对比

Abstract: Carbon isotope composition of liquid hydrocarbons formed in different stages of gvolution of kerogen is determined by thermal simulation experiments on immature kerogen.The cause of fractionation of carbon isotope in the crude during the process of evolution is given,and the "reverse reactions" in the carbon isotope composition of kerogen in the matrix and of crude oil formed during the highly mature sta ge is identified and explained.It is pointed out that in the application of carbon isotope to the comparative study of crude oil and its source in the multizone regions,care should be taken that the comparison of the degree of evolution is valid only for kerogen or oil of the same stage of evolution,particularly for those from the highly mature regions,otherwise it may lead to misleading conclusions.