成岩作用阶段某些生物标志物的分布特征

DISTRIBUTION OF SOME BIOMARKERS IN DIAGENETIC STAGES

史继扬 汪本善 张丽洁 洪紫青 辛茂安

Shi Jiyang Wang Benshan Zhang Lijie Hong Ziqing Xin Mao'an

我国一些第三系盆地已发现了许多低成熟原油。作者研究了东濮凹陷岩心剖面,并对低成熟生油岩进行了热模拟实验,发现生物标志物随埋藏深度增加,按藿烯、ββ-藿烷、重排甾烯的次序先后消失后,升藿烷构型变化才开始达到平衡。热模拟实验证实某些生油岩在成岩作用阶段可以生成一些低成熟原油。在此阶段生成的三环萜烷倾向于富集在原油之中,低分子量三环萜烷相对于高分子量三环萜烷的丰度可以用来详细划分成岩作用阶段。

Immature oil has been found in a number of Tertiary basins in China.The authors studied the core profiles of the Dongpu Depression in Henan Pro-vince and made thermo-degradation experiment on immature source rocks. Itis found that after hopenes, ββ-hopanes and rear rangment sterenes disappeared successively with the increase of buried depth, the configuration of homo-hopanes came to reach equilibrium. Thermal simulation experiment has pro-ved that lower matured crude oil might be generated from some kinds ofsource rocks during diagenetic stage. The tricyclic terpanes generated in thisstage had the tendency to concentrate in crude oil. The abundance ratio oflower-molecular-weight tricyclic terpanes to higher ones can be used to sub-divide diagenesis.

10.11743/ogg19880302