沈家铺油田枣Ⅴ油组原油地球化学特征

对沈家铺油田枣V油组原油有机地球化学特征进行了详细描述,并对母源沉积环境、生源及生油岩演化程度进行了分析。研究结果表明,原油中饱和烃的含量低,非烃沥青质含量高,类异戊二烯烷烃含量高,奇碳数优势弱,成熟度参数低,这些都表明原油具有低成熟度的特点。Pr与Ph含量的比值低(0.66～0.88),伽马蜡烷与C31藿烷含量的比值高(0.59～0.86),这反映出其源岩形成于微咸水—半咸水湖相还原环境。其生油源主要由菌藻类有机质组成,但藻类可能是其源岩有机质的主要贡献者。

Geochemical characteristics of crude oil in Zao V measure of Shenjiapu Oilfield

The geochemical characteristics of crude oil of Zao V measure in the Shenjiapu Oilfield were systematically described. The sedimentary environment, property of crude oil and evolution of oil source rock were also discussed. All facts such as low-saturated hydrocarbon content, high content of resin and asphalt, rich isoprenoids, slight odd-even preference and low-maturity steranes and terpanes parameters show that these oils are just in an early matured stage. Low containing ratio of Pr-to-Ph ranging from 0.66 to 0.88 and high containing ratio of gammacerane-to-C_(31) hopanes ranging from 0.59 to 0.86 indicate that oil resource rock was generated in the sedimentary environment from slight saline to half saline reductive lake. Crude oil is mainly derived from bacteria and algae, which is perhaps the main contribution of organisms.