渤海湾盆地黄骅坳陷滨海Ⅰ号构造原油的油源研究及意义

THE OIL SOURCE AND ITS SIGNIFICANCE FOR PETROLEUM EXPLORATION IN STRUCTURAL BELTⅠIN THE HUANGHUA DEPRESSION, THE BOHAI BAY BASIN

王新海 苏峻青 曹延 付立新 王莉 肖枚 郭金风

Wang Xinhai Su Junqing Cao Yan Fu Lixin Wang Li Xiao Mei Guo Jinfeng

长江大学, 地球科学学院, 湖北, 荆州, 434023 2. 中国石油大港油田公司, 油气勘探开发研究院, 天津, 300280

College of Geoscience, Yangtze University, Jingzhou, Hubei 434023, China 2. Oil and Gas Exploration and Development Institute, Dagang Oil Field Branch, PetroChina, Tianjin 300280, China

滨海Ⅰ号构造是渤海湾盆地黄骅坳陷歧口凹陷勘探程度很低的大型构造,所钻探的白东2×1井东营组发现低产油流。原油地球化学特征研究表明,该原油为中高蜡轻质成熟原油,甾烷组成中以胆甾烷和异胆甾烷为主,且C27,C28,C29甾烷呈略不对称的"V"型分布,有一定量的重排甾烷和4-甲基甾烷;萜烷组成中三环萜烷略低于五环萜烷,伽马蜡烷高,Ts,C29Ts和C30重排藿烷含量相对较高。生物标志物分布特征表明该原油的生烃母质具有菌藻类和陆源高等植物混合特点,且沉积于半咸水—咸水环境,应该来源于歧口凹陷沙一下段或沙三段咸水湖相烃源岩。滨海Ⅰ号构造紧邻歧口生油凹陷,油气成藏条件好,具有良好的勘探前景。

Some stripped oil stream has been found in Dongying Formation in the Well Baidong 2×1 lying in the structural belt Ⅰ of the Huanghua Depression,the Bohai Bay Basin.The structural belt Ⅰ is large in scale with lower degree of exploration.The geochemical characters of the crude oil showed that the oil was a light and mature crude oil with middle-high content of wax.The primary gonane components are cholane and isocholestane,and the distribution of the C27,C28 and C29 gonane is just like of an appreciably anisomerous "V".And the secondary gonane components are some diasteranes and 4-methyl gonane.The content of tricyclic terpane is appreiably lower than that of pentacyclic terpane.The content of gammacerane is high.And the content of Ts,C29Ts and C30 rearrangement hopanoid is higher.The distribution character of biomarkers shows that oil source is a mixture of homoneneae and terrigenous plants in brackish-saline water.This indicates that the crude oil was originated from the saline lake source rock in the lower Es1,or Es3 in the Qikou Sag.Structural belt Ⅰ is close to the petroleum generative sag,and the reservoirs conditions are good,so it's favorable for petroleum exploration.

https://doi.org/10.11781/sysydz200805499