小板凹陷未熟油地球化学特征与油源探讨  

THE GEOCHEMISTRY OF THE IMMATURE OIL AND SOURCE CORRELATION IN XIAOBAN DEPRESSION

作　　者：童小兰[1] 

机构地区：[1]中国地质大学能源学院

出　　处：《资源环境与工程》2006年第1期19-22,51,共5页Resources Environment & Engineering

摘　　要：通过对小板凹陷烃源岩及原油样品的有机地化分析,研究该区未熟油的地球化学特征,探讨未熟油油源。认为小板凹陷原油具有“高密度、高粘度、高含硫”的特征,生油岩和原油的饱和烃含量低,“非烃+沥青质”含量高,正烷烃呈“前峰型”或“前高双峰型”分布。具植烷优势,Pr/Ph<0.2。萜烷以伽玛蜡烷含量高,Tm/Ts>1为特征。根据镜质体反射率指标、孢粉颜色及颜色指数、生物标记化合物指标等综合判断小板凹陷生油岩为未熟烃源岩,原油为未熟油,油源对比研究表明该未熟油来源于潜江组未熟烃源岩,因此该凹陷的油气勘探方向应立足未熟油的勘探。Geochemical characteristics and Origin of immature oils are discussed in terms of organic geochemistry of crude oil and source rocks from the Xiaoban depression. Crude oils from the depression are characterized by the high density,high viscosity, high sulfur contents, the low contents of saturated hydrocarbons and the great abundances of non- hydrocarbons and asphaltenes. N -alkanes in the oils display a leading peak or leading high himodal carbon number pattern with an odd - over - even predominance. The ratio of pristine/phytane is less than 0. 2 while the phytane is preponderant. The terpanes are characterized by the high ganlnlacerane and tile ratio of Ts/Tm is greater than 1. The indices of vitrinite reflectance, sporinite colour and biomarks show that the source rocks and the crude oil from the Xiaoban depression are immature. The oil source correlation show that the immature oil is from the immature source rock of Qianjiang Formation. So the exploration direction of the depression should be be on immature oil.

关 键 词：未熟生油岩 未熟油 地球化学特征 油源对比 潜江组 小板凹陷 

分 类 号：TE132.14[石油与天然气工程—油气勘探]