摘要
松辽盆地西部斜坡北段油气主要来自齐家—古龙生油凹陷青山口组烃源岩,油气沿着高台子油层和萨尔图二-三油层砂体以狭窄的路径侧向西运。共发育3条运移路径,侧向运移的油气受低幅度构造、断层和地层尖灭遮挡富集成藏。西部斜坡构造幅度较低,断层规模小,平面延伸的距离短,不利于油气大规模聚集成藏,盆地边部的地层超覆带是寻找大规模地层尖灭油气藏和油砂矿的有利地区。斜坡区普遍受大气降水淋滤作用,原油受喜氧细菌的降解作用普遍稠化,沿着大气水下渗方向,原油稠化的程度越来越低,造成自西而东原油性质呈现规律性变化:地层超覆带为严重降解的稠油和油砂,断层遮挡油气聚集带为中等降解的稠油,构造—岩性油气聚集带为轻度降解的稠油和正常原油。
The oil and gas in northern sector of the West hankou Formation in the Qijia-Gulong Sag, Central Slope, Songliao Basin, sourced from Qings- Depression, which laterally migrated westwards along 3 narrow pathways, and accumulated by the low-amplitude structures, barrier of faults and stratigraphic pinch outs. In the West Slope,the oil and gas were not favored to enrich in large scale, since the structures＇ amplitude being usually lower, the scale of the faults being smaller and the stretching distance of the faults being short. The stratigraphic overlap belt along the basin margin might be a favorable area to find large-scale stratigraphic pinch out accumulations and oil sand mines. The atmospheric water eluviation was pervasive in the West Slope,where the crude oils were generally degradated by the aerobic bacteria and the degree of the densification became lower along the direction of the atmospheric water descending, namely, the seriously degradated heavy oil and oil sand developed in the stratigraphic overlap belt along the basin margin,moderately degradated heavy oil developed in the fault barriered oil accumulation belt,while the lightly degradated heavy oil and normal oil occurred in structural-lithologic oil accumulation belt. The oil sand mines in Tumuji and Well Lai D6 showed more prospects to the exploration in the West Slope.
出处
《地质科学》
CAS
CSCD
北大核心
2009年第2期478-489,共12页
Chinese Journal of Geology(Scientia Geologica Sinica)
基金
国家重点基础研究发展计划(编号:2009CB219308)资助
关键词
油源
侧向运移
聚集条件
稠油
西部斜坡
松辽盆地
Oil source, Lateral migration, Accumulative conditions, Heavy oil, The West Slope,The Songliao Basin
