抚顺盆地始新世计军屯组油页岩贫富矿成矿机制  

High grade and low grade oil shale metallogenic mechanism of Eocene Jijuntun Formation in Fushun Basin

作　　者：柳蓉[1] 刘招君[1] 刘沣[1] 孟庆涛[1] 史冀忠[1] 张健[1] 杜江峰[1] 

机构地区：[1]吉林大学地球科学学院,吉林长春130061

出　　处：《大庆石油地质与开发》2008年第2期47-50,96,共5页Petroleum Geology & Oilfield Development in Daqing

基　　金：自然科学基金项目(40672075);高等学校博士学科点专项科研基金(20050183051)资助

摘　　要：综合利用野外露头、岩石矿物组合、有机岩石学、元素地球化学等特征分析认为,抚顺盆地油页岩为湖相成因。该组油页岩上、下段含油率差别很大,上段富矿层发育大量结核,下段贫矿层发育大量的大植物化石和动物化石;油页岩段富矿有机质类型为I—II1型,而贫矿为II2型;w(V)/w(V+N i)在油页岩贫矿和富矿段均大于0.60,说明其处于厌氧的沉积环境,但富矿层比值明显大于贫矿层;w(N i)/w(Co)和w(V)/w(N i)在富矿油页岩表现非常稳定,在贫矿过渡为富矿过程中突然增加,并且一直保持到该段结束;油页岩段贫矿中陆源碎屑矿物含量以及Ti、Cu、Li、Rb、Pb、Ga、Cr、Zn等外源元素较富矿富集。研究表明油页岩段富矿为半深湖—深湖沉积,贫矿为浅湖沉积,正是由于两者沉积环境的差异导致了该组油页岩的贫富差距。Fushun Basin is a residual fault basin of Cenozoic and no border facies have been found around it. With the comprehensive application of outcrop, mineral assemblage of rocks, organic petrology and geochemistry characteristics analysis, it is found that the oil shale in Fushun Basin belongs to lacustrine origin. There is great difference between the oil bearing rates for upper member and lower member in the oil shale of this formation. In upper high grade oil layer, a large quantity of accretions are grown, and in lower low grade oil layer phytolite and animal remains are grown. The type of organic matter for high grade oil shale is kerogen Ⅰ-Ⅱ1, and that for low grade oil shale is kerogen Ⅱ2. The ratios of V/ （ V ＋ Ni） for poor rock and pay lead are higher than 0. 6, which suggests an anaerobic deposition environment. But the ratio for pay lead is higher than that for poor rock. Ratios of Ni/Co and V/Ni are steady in high grade oil shale layer, but it increases abruptly from pay lead zone to poor rock layer till the disappearance of the interval. The contents of the land source detrital mineral and Ti, Cu, Li, Rb, Pb, Ga, Cr, Zn and other exogenous elements are rich in low grade oil shale. According to the research, it is sub-deep lacustrine and deep lacustrine deposition for the high grade oil shale interval, it is shallow lacustrine deposition for the low grade interval, and it is the difference in depositional environment that results in the difference between the high grade and low grade oil shale in this Formation.

关 键 词：抚顺盆地 油页岩 湖相成因 贫富矿成矿机制 沉积环境差异 

分 类 号：TE122[石油与天然气工程—油气勘探]