摘要
陆东凹陷上侏罗统九佛堂组生油岩的地化分析资料表明，其生物标志物的组成和分布与沉积环境的水介质条件和氧化还原性密切相关。以广发背斜带为界，凹陷西部生油层中正构烷烃在Ｃ１５～Ｃ１９呈明显的奇偶优势；类异戊二烯烃异常丰富，Ｐｒ／Ｐｈ大多小于０．５；缺少重排二环倍半萜烷和重排甾烷；富含伽马蜡烷和胡萝卜烷及Ｌｅｘａｎｅ化合物；芳烃中有较高的脱羟基维生素Ｅ系列，表征微咸水强还原的沉积环境。凹陷东部生油岩中的Ｐｒ／Ｐｈ多大于１．０；富含重排甾、萜类化合物；少含伽马蜡烷和胡萝卜烷系列化合物，反映弱氧化淡水沉积环境。
Geochemical data of Jiufutang Formation (upper Jurassic) source rocks in Ludong depression, Kailu basin reveals that the composition and distribution of biomakers are related to the water nature and oxidation-reduction of depositional environment. The saturated hydrocarbons of source rock samples from the western part of the depression show n-alkanes distribution with an odd carbon number predominance (C15 ￣C19), abundant isoprenoids (Pr/Ph<0.5 in most samples), absence of rearranged bicyclanes and diasteranes, and high amount of gammacerane and carotenoids. Their aromatic fractions contain relatively high amount of methylated MTTCs. These composition characteristics suggest brackish water and reducing depositional environment. In contrast, the source rocks in the eastern part of the depression have Pr/Ph values of more than 1.0, abundant rearranged bicyclanes, hopanes and diasteranes, and low amount of gammacerane and carotenoids, reflecting oxidic fresh lake depositional environment.
出处
《江汉石油学院学报》
CSCD
北大核心
1996年第3期29-34,共6页
Journal of Jianghan Petroleum Institute
关键词
有机地球化学
生物标志物
生油层
沉积环境
organic geochemistry
biological marker
source bed
sedimentary environment
Lujiapu seg
