沾化凹陷罗家地区沙三下亚段页岩地球化学特征及其评价

Geochemical Characteristics of Shale in the Es3L of Shahejie Formation in Luojia Area of Zhanhua Sag and Its Evaluation

摘要: 通过对有机质丰度、有机质类型、有机质成熟度的特征进行详细研究，综合分析了沙三下亚段(Es₃^L)页岩地球化学特征并对其进行了评价。研究结果表明，在有机质丰度上，Es₃^L页岩总有机碳质量分数(w(TOC))和氯仿沥青“A”(w(“A”))质量分数均较高，是页岩油的主要富集层位；在有机质类型上，有机质显微组分和热解烃质量分数w(S₂)~w(TOC)线性回归均表明Es₃^L页岩有机质类型为I型，具有较好的生油潜力；在有机质成熟度上，镜质体反射率和最高热解峰温均表明Es3L页岩中的有机质处于成熟阶段，正在大量生油。

Abstract: The geochemical characteristics of shales in Es₃^L of Zhanhua Depression were studied and evaluated through analyzing the abundance, type and maturity of the organic matter in detail. Study indicates that the Es₃^L shales provide main accommodation for oil, which is evidenced by high mass factors of w(TOC) and chloroform bitumen w(“A”). The Es₃^L shales are dominated by Type I Organic Matter; they are high oil-generating potential, which is evidenced by the microscopic components and the w(TOC) linear regression for w(S₂) (pyrolysis hydrocarbon). The organic matter of the Es₃^L shales is so mature that they can generate a large volume of oils, which is illustrated by the vitrinite reflectance and the highest thermal pyrolysis peak temperature.