辽河盆地东部凹陷欧利坨子地区原油性质与成因

CHARACTERISTICS AND ORIGINS OF THE CRUDE OIL IN OULITUOZI AREA OF THE EAST SAG, THE LIAOHE BASIN

周陆扬 刘怀山 姜建群 金祥纯

Zhou Luyang Liu Huaishan Jiang Jianqun Jing Xiangchun

中国海洋大学, 海洋地球科学学院, 山东, 青岛, 266003 2. 中国石油天然气集团公司辽河石油勘探局物探公司, 辽宁, 盘锦, 124010 3. 中国石油天然气股份有限公司辽河油田海南油气勘探分公司, 辽宁, 盘锦, 124010

College of Marine Geosciences, Ocean University of China, Qingdao, Shandong 266003, China 2. Geophysical Exploration Company of Liaohe Petroleum Exploration Bureau, CNPC, Panjing, Liaoning 124010, China 3. Hainan Oil and Gas Exploration Branch Company, Liaohe Oilfield, PetroChina, Panjing, Liaoning 124010, China

油—油精细对比揭示辽河盆地欧利坨子地区低熟油和成熟油共存,与东部凹陷其它地区原油相比总体上成熟度较低.表现在原油族组成中饱和烃和饱芳比值低(饱/芳值小于3.0)、生物标志物中反映成熟度的参数明显偏低、饱和烃和芳烃碳同位素值(分别为-26.00‰~-27.50‰和-25.00‰~-26.50‰)也明显低于东部凹陷其它地区,单体烃碳同位素类型曲线特征也揭示其原油成熟度较低.油—源对比揭示欧利坨子地区原油来自沙三中下段的暗色泥岩,生物标志物资料揭示源岩热演化程度明显低于东部凹陷其它地区,因而造成该区原油成熟度较低.

Oil-oil meticulous correlation research shows that there exist both immature and mature oils in Oulituozi area of the Liaohe Basin,and the maturity level of these oils is generally lower than those in the other areas of the East Sag.The lower maturity level of the oils in Oulituozi area is reveald by the following aspects:the ratio of saturated to aromatic hydrocarbons is low(3.0),the values of the maturity parameters of biomarkers and the stable carbon isotope values of saturated hydrocarbons and aromatics(-26.00‰～-27.50‰ and -25.00‰～-26.50‰ respectively) are also lower respectively than those in the other areas of the East Sag.The characteristics of the isotope contours of various individual hydrocarbons also indicates that the maturity of the oil in Oulituozi area is low.The results of oil-source correlation research suggest that the crude oil in Oulituozi area comes from the dark mudstone layers of the middle and lower parts of the 3rd member of Shahejie Formation,and the results of biomarker research show that the thermal evolution degree of the source rocks in Oulituozi area is apparently lower than those in the other areas of the East Sag,which causes the low maturity of the crude oil in the area.

国家自然科学重点基金项目(40238059)

https://doi.org/10.11781/sysydz200705490