白音查干凹陷西洼低熟油特征及成藏规律  

Characteristics and pool-forming regularity of immature oil in western Baiyinch agan depression, Erlian basin.

作　　者：赵广珍[1] 张家政[2] 张源智[1] 闫东育[2] 宋治霞[1] 牛小芳[1] 

机构地区：[1]中原油田分公司勘探开发科学研究院 [2]中原石油勘探局地质录井处

出　　处：《石油勘探与开发》2001年第5期4-7,共4页Petroleum Exploration and Development

摘　　要：二连盆地白音查干凹陷西洼白垩系低成熟原油主要见于埋深小于 10 0 0m的都红木组都一段 ,与同地区成熟油的芳烃和沥青质含量相似 ,但饱和烃含量低、非烃含量高。西洼白垩系低成熟原油的正构烷烃中奇偶优势明显 ,Pr/Ph值多小于 0 .6,Pr/nC18值大于 2 .3 7,C2 92 0S/(2 0S + 2 0R)值小于 0 .3 ,C2 9ββ/(ββ +αα)值小于 0 .3 5 ,C3 12 2S/(2 2S + 2 2R)值小于 0 .5 ;ααα 2 0RC2 7/C2 9、ααα 2 0RC2 8/C2 9比值及碳同位素特征均显示 ,凹陷内成熟原油与低成熟原油来自相同的油母质。低熟油成藏具有早生、早排、成藏期晚、运移距离短等特点 ,断裂是成藏的主要控制因素 ,低熟油气主要分布于三角洲前缘及三角洲前方滑塌浊积扇中。Cretaceous immature oil in west part of Ba iyinchagan depression appears mainly in the first Member of Douhongmu Formation with abundant soluble and good organic matter at a depth less than 1000m. Compar ed to the mature oil discovered in the same area, its aromatic and asphaltic con tents are similar to that of the latter, while its non-hydrocarbon content is h igher and saturated hydrocarbon content is lower. It has a significant odd-even predominance in normal alkane series. Its Pr/Ph value is low (<0.6), and Pr /nC 18 value is high (>2.37). C 29 20S/ (20S+20R) is less than 0.30, C 29ββ/(ββ+αα) is less than 0.35, C 3122S/(22S+22R) is less t han 0.5. The value of ααα-20RC 27/C 29,ααα-20RC 28 /C 29and the characters of carbon isotope show that mature and immature o il came from the same oil-kitchen. Immature oil is characterized by early gener ation, early expelling, late formation of oil pool and short distance migration. The accumulation and pooling of oil were controlled by the fracture. It is foun d that oil pools are mainly distributed in the sand bodies of delta-front and s lump turbidity in the front of the delta.

关 键 词：白音查干凹陷 低熟油 特征 成藏规律 油气勘探 

分 类 号：P618.130.2[天文地球—矿床学] TE12[天文地球—地质学]