摘要
准噶尔盆地东部地区存在 4套烃源岩 ,其中 ,二叠系烃源岩生烃潜力大 ,是最好也是最主要的烃源岩 ;三叠系烃源岩次之 ;侏罗系和石炭系烃源岩有机质类型以Ⅲ型为主 ,丰度变化大 ,生烃潜力低于二叠系和三叠系。这 4套烃源岩在埋藏浅的地区尚处于未成熟或低成熟阶段 ,但在阜康凹陷均达成熟%D高成熟阶段 ,具备了生成大量原油的热演化条件。 4套烃源岩抽提物生物标志物组成特征差异明显 ,二叠系烃源岩以富含 β 胡萝卜烷、伽马蜡烷、C2 8和C2 9甾烷、几乎不含重排甾烷以及C2 7甾烷含量很低为主要特征 ;三叠系抽提物以富含Ts、C2 9Ts和重排甾烷以及伽马蜡烷含量低为主要特征 ;侏罗系烃源岩抽提物碳同位素明显重于二叠系和三叠系 ,δ13 C值一般大于 -2 8‰ ,Pr/Ph值一般大于 3 .0 ,以富含五环萜烷、C2 9甾烷和贫三环萜烷、伽马蜡烷、C2 7和C2 8甾烷为主要特征。图 3表 2参 2
Four hydrocarbon source rocks, in age of Carboniferous, Permian, Triassic, and Jurassic developed in the east of the Junggar Basin, Northwest China. The geochemical study shows that Permian source rocks, which contain high abundances of organic matter with good genetic potential, are the best hydrocarbon source rocks, and then, the Triassic source rocks in this area. The organic matter in Jurassic and Carboniferous source rocks mainly compose of type Ⅲ kerogen and their abundance varies greatly, for which the genetic potential is lower than that of Permian and Triassic rocks. These four source rock units in the Fukang Sag all reach a mature high mature stage and have generated large amounts of oil. Permian extracts are isotopically lighter, and have low Pr/Ph ratios, are rich in β carotane, tricyclic terpenes, gammacerane and C 28 and C 29 steranes, contain almost no diasteranes and have a low content of C 27 steranes. Triassic extracts are characteristically rich in Ts, C 29 Ts and diahopanes, but have low gammacerane contents. The carbon isotopic composition of Jurassic extracts is noticeably heavier than that of Permian and Triassic extracts. Jurassic source rocks have Pr/Ph ratios generally > 3.0, and are rich in pentacyclic hopanes and C 29 steranes, but poor in tricyclic terpenes, gammacerane, and C 27 and C 28 steranes.
出处
《石油勘探与开发》
SCIE
EI
CAS
CSCD
北大核心
2003年第4期20-24,共5页
Petroleum Exploration and Development
基金
国家自然科学基金 ( 4 9873 0 0 1)
中国石油天然气股份有限公司科技项目 ( 0 10 10 9 3 )
