Simulation Experiment of Generation and Migration of on Generated from coal: Ⅲ. Characteristics of Biomarkers of Sterane and Terpane and Their Significance

Based on data acquired from a pressurized thermal simulation experiment (T = 270℃ ～390℃) in which both oil generation and expulsion from two brown coals are inspected, the characteristics of sterane and terpane products are studied in this paper. The results indicate:(1) The abnormal enrichment of C₃₁ +components in hopane series may be related to a strong reducing environment, and their abnormal lack may have something to do with an oxidation environment. (2) Because the activation energy of isomerization of sterane and hopane is lower than that of vitrinite, the isomerization rates of sterane and hopane are much faster than that of vitrinite in geological low temperature, but the situation is converse in the condition of high temperature of laboratory. (3) Many ratios in sterane or terpane related to the difference of molecular size can be acted as migration parameters.