热模拟实验过程中生物标记物的演化

THE EVOLUTION OF BIOMARKERS IN PROCESS OF THERMAL SIMULATION

本文对两个未成熟泥岩样品进行了不同成熟度系列的热模拟实验,对其残渣氯仿抽提物之饱和烃中生物标记物的研究发现:①生物标记物立体异构化过程中除温度这一重要作用因素外,时间也是不能忽视的重要因素;②4-甲基甾烷由4β(CH_3)构型转化成4α(CH_3)构型,在未成熟阶段是较好的成熟度参数,而且4-甲基甾烷不会随成熟度增加而转化成正常甾烷;③五环三萜烷的分布受热演化程度的影响,不同的成熟度分布不同。莫烷在成熟过程中先增加然后再减少;④三环萜烷丰度与原始母源输入有关,与五环萜烷裂解无关。

In this paper,it is found from a study of the biomarkers in the chloroform extract in the residum obtained from a thermal simulation of two samples that:(1)in addition to the important factor-temperature,time is another important factor that can not be neglected in the stereo isomerization of the biomarkers;(2)the alteration of 4-methyl sterane from a 4β(CH_3)configuration to a 4a(CH_3)is a better maturity parameter in the premature stage,and moreover,4-methyl sterane will not alter to normal sterane as the degree of maturity becomes higher;(3)the distribution pentacyclic-tri-terpane is affected by the stage of thermal evolution,and is different for different degree of maturity,mortane is in- creased first and then decreased;(4)the abundance of 3 ring terpane is related to the orig- inal source material,and is independent to the cracking of the pentacyclic terpane.