博格达地区芦草沟组页岩油散失量研究  

Shale Oil Loss of Lucaogou Formation in Bogda

作　　者：王圣柱[1] Wang Shengzhu(Sinopec Shengli Oilfield Branch Company,Dongying,Shandong 257015,China)

机构地区：[1]中国石化胜利油田分公司,山东东营257015

出　　处：《特种油气藏》2020年第3期74-81,共8页Special Oil & Gas Reservoirs

基　　金：国家科技重大专项“准噶尔盆地碎屑岩层系油气富集规律与勘探评价”(2016ZX05002-002);中石化科技攻关课题“山前带油气成藏规律及目标评价”(P17001-3)、“准东南地区二叠系油气地质条件及勘探潜力”(P18054-2)。

摘　　要：页岩油散失是叠合盆地复杂构造区页岩油资源评价中的薄弱环节。保存条件研究对页岩油散失的影响及其量化表征以及对于叠合盆地"残留"页岩油资源的科学评价及勘探具有重要的现实意义。以准噶尔盆地博格达地区中二叠统芦草沟组为例,以大量露头和岩心样品的岩石薄片、全岩X衍射、有机碳及热解等测试资料为基础,对芦草沟组泥页岩层系开展岩性岩相特征、储集特征、有机地球化学特征、含油性及保存评价单元等方面的研究,建立不同岩相、不同保存评价单元的有机质丰度与含油率关系模型,采用相对保存系数对页岩油散失量进行量化表征。结果表明:芦草沟组发育凹陷区、构造稳定区、冲断改造区和地表出露区4类保存评价单元,并发育基质型和夹层型2种页岩油岩相类型;储集空间、孔隙结构及保存条件控制了不同岩相储层的含油性差异,基质型岩相有机碳含量与含油率为幂函数关系,夹层型岩相两者为线性函数关系;建立了不同评价单元基质型和夹层型岩相页岩油的相对保存系数权重量化赋值模型,实现了页岩油散失量的量化表征。研究成果为复杂构造区页岩油资源量评价提供了一种思路方法。Shale oil loss is considered as a weak link in the shale oil resource evaluation of complex structural area of superimposed basin.Preservation condition identification shows a practical significance for the quantitative characterization of shale oil loss,evaluation and exploration of the residual shale oil resources in the superimposed basin.The lithologic facies,reservoir properties,organic geochemical properties,oil-bearing properties and preservation evaluation unit were investigated for the Middle Permian Lucaogou Formation of Bogda in Junggar Basin.A large number of thin-section analysis for the outcrop and core samples,whole rock X-ray diffraction,organic carbon and pyrolysis data were used to establish the models between organic matter abundance and oil content in different lithologic facies and different preservation evaluation units.A relative preservation coefficient was introduced to quantitatively characterize the shale oil loss.Result indicates that there are four categories of preservation evaluation units in the Lucaogou Formation,including depression zone,stable structure zone,thrust reformation zone and surface exposure zone.There are also two types of shale oil facies in the Lucaogou Formation,including matrix and interlayer lithologic facies.The reservoir space,pore structure and preservation condition determine the oil-bearing properties of different lithologic facies.The oil content shows a power relationship with the organic carbon content for the matrix lithologic facies.The oil content presents a linear relationship with the organic content for the interlayer lithologic facies.A quantitative weighting model of relative preservation coefficient for the matrix and interlayer lithologic facies of different preservation evaluation units was established to quantitatively characterize the shale oil loss.This research could provide a method for the evaluation of shale oil resources in complex structural areas.

关 键 词：页岩油 保存评价单元 保存系数 页岩油散失 准噶尔盆地 博格达地区 芦草沟组 

分 类 号：TE122.1[石油与天然气工程—油气勘探]