东营凹陷北部沙四段下亚段盐湖相烃源岩特征及展布  

Characteristics and distribution of salt lake source rocks from lower submemeber of 4th member of Shahejie formation, north Dongying depression

作　　者：高阳[1] 

机构地区：[1]中国石化胜利油田分公司地质科学研究院,山东东营257015

出　　处：《油气地质与采收率》2014年第1期10-15,111,共6页Petroleum Geology and Recovery Efficiency

基　　金：国家自然科学基金项目"咸化湖盆优质烃源岩形成及其有机质与盐类物质相互作用研究"(405272084);国家科技重大专项"渤海湾盆地精细勘探关键技术"(2011ZX05006)

摘　　要：对东营凹陷北部沙四段下亚段盐湖相烃源岩特征及展布缺乏系统研究,尤其对盐湖沉积物中普遍发育的含膏泥岩、含盐泥岩、膏质泥岩和盐质泥岩的生烃潜力认识不清。首先利用有机碳、岩石热解等实验分析手段,对不同岩相烃源岩的生烃潜力进行研究;然后基于实验分析数据,建立了盐湖相烃源岩有机碳含量测井评价模型,利用评价结果分析了烃源岩展布特征,结合埋藏史和热演化史研究了烃源岩生烃史。结果表明:研究区沙四段下亚段烃源岩有机质以腐泥型为主,有机质类型主要为I—II1型,少量为II2型,都是优质的生油母质;证实了含膏泥岩、含盐泥岩、膏质泥岩和盐质泥岩都具备生烃潜力,可孕育有效烃源岩。民丰地区、利津地区和胜坨下降盘是有效烃源岩发育的有利位置,这些地区有效烃源岩累积厚度大,有机碳含量高。研究区沙四段下亚段烃源岩普遍经历了"快—慢—快"的埋藏过程,生油高峰持续时间长,目前处于烃源岩热解和原油裂解生气阶段,有利于烃源岩热解气和原油裂解气成藏。The characteristics and distribution of salt lake hydrocarbon source rocks from lower submember of 4th member of the Shahe-jie formation is short of systematic research. Especially, the hydrocarbon potential of halopelite, gypsum mudstone which are widely de-veloped in salt lake, is less understood. In response to these problems, multiple source rock samples of study layer are collected and an-alyzed. The experimental results confirmed that, the source rocks interbedded with the gypsum or salt are rich in organic matter, andthe type of organic matter in source rocks is mainly II1-I, which is of great oil generation potential. The experiments also confirmed thehalopelite, gypsum mudstone have certain hydrocarbon potential, and can function as effective hydrocarbon source rocks. Based on theexperiment data, the evaluation methods of salt lake source rocks by logging information are established and the distributions of hydro-carbon source rocks are studied. Results show that, the effective source rocks are mainly distributed in Minfeng area, Lijin sag anddownthrown of Shengtuo area. The source rocks in these areas have great total thickness, high organic carbon content. Finally, the evo-lutions of source rocks are analyzed. The source rocks of lower submember of 4th member of Shahejie formation generally experienceda'fast-slow-fast'burial history, and experienced long oil generated period. At present, the source rock generated wet or dry gas due tothe thermal effect, and the crude oil in source rocks and ancient reservoirs started to crack and generate gases.

关 键 词：盐湖烃源岩 含膏泥岩 含盐泥岩 膏质泥岩 测井评价 东营凹陷 

分 类 号：TE112.113[石油与天然气工程—油气勘探]