济源盆地上三叠统谭庄组油页岩段构造裂缝特征及主控因素分析  

Characteristics and main factors controlling development of tectonic fractures in Oil-Shale Member of Upper Triassic Tanzhuang Formation in Jiyuan Basin

作　　者：孙长彦[1,2] 王志远 李振峰 张勐 杨恒 SUN Changyan;WANG Zhiyuan;LI Zhenfeng;ZHANG Meng;YANG Heng(School of Resources and Environment,Henan Polytechnic University,Jiaozuo 454000,China;Collaborative Innovation Center of Coalbed Methane and Shale Gas for Central Plains Economic Region,Jiaozuo 454000,China;School of Energy Science and Engineering,Henan Polytechnic University,Jiaozuo 454000,China)

机构地区：[1]河南理工大学资源环境学院,河南焦作454000 [2]中原经济区煤层(页岩)气河南省协同创新中心,河南焦作454000 [3]河南理工大学能源科学与工程学院,河南焦作454000

出　　处：《煤炭科学技术》2022年第7期206-215,共10页Coal Science and Technology

基　　金：国家自然科学基金资助项目(41472127);河南省自然科学基金资助项目(182300410004)。

摘　　要：济源盆地上三叠统谭庄组油页岩段厚约140 m,埋藏深度一般为3000~7000 m,主要由油页岩、泥岩、粉砂质泥岩和粉砂岩组成,是济源盆地最有利的页岩油气勘探开发层段。查明该区目标层段构造裂缝发育特征及其主控因素,可为该区页岩油气勘探开发提供依据。通过露头观测、取样和实验室测试,对目标层段的烃源岩特征、构造裂缝特征和构造裂缝发育的主控因素进行了研究。研究发现:济源盆地上三叠统谭庄组油页岩段油页岩脆性矿物含量为37.4%~77.9%,平均为53.7%;总有机碳含量为0.36%~10.33%,平均为4.13%;镜质体反射率为1.01%~2.12%,平均含量为1.33%;有机质类型主要为腐植—腐泥质型。该区油页岩段发育有剪裂缝、张裂缝、顺层滑移裂缝和复合型裂缝4种类型的构造裂缝;裂缝穿层性较强,总体以垂直缝和与岩层面高角度斜交缝为主;以宽度主要为0.01~2 cm的部分充填或未充填裂缝为主;裂缝平均线密度为6.29条/m,且随着岩石粒度变细而增大、随着脆性矿物含量的增加而增大、随着岩层厚度的增加而减小、越接近断层越发育。研究结果表明:研究区目标层系油页岩层具有较高的生气潜力和较强的可改造性,且较为发育的构造裂缝为油气的储集和运移提供了空间,济源盆地上三叠统谭庄组油页岩段具有良好页岩气的勘探开发前景。The Oil-Shale Member in the Upper Triassic Tanzhuang Formation in the Jiyuan Basin is about 140 m thick and generally buried at a depth of 3000 m and 7000 m.It is mainly composed of oil shale,mudstone,silty mudstone,and siltstone.This is the most favorable shale deposit for oil and gas exploration and exploitation in the Jiyuan Basin.Identifying the development characteristics of structural fractures and their main controlling factors in the target interval in this areacan provide the basis for the exploration and development of shale oil and gas in the region.In this paper,through outcrop observation,sampling and laboratory testing,the source rock characteristics,tectonic fracture characteristics,and the main controlling factors of fractures of the target oil-shale Member in the study area were studied.The results show that the brittle-mineral contents of the oil shale in the oil shale section of the Upper Triassic Tanzhuang Formation in the Jiyuan Basin ranges from 37.4%-77.9% with an average of 53.7%,and the total organic carbon content is from 0.36% to 10.33%,with an average of 4.13%;The reflectivity of vitrinite ranges from 1.01% to 2.12%,with an average content of 1.33%.The organic matter type is mainly humic-saprolite type.There are four types of tectonic fractures in the study area,e.g.shear,tensile,bedding-slip,and compound fractures.These fractures are mostly vertical or intersect the bedding at high angles.It is dominated by partially filled or unfilled fractures with a width of 0.01-2 cm;the average linear density of fractures is 6.29 strip/m,and it increases with the finer grain size of the rock and with the increase of the brittle mineral content,decreases with the increase of rock thickness,and the closer to the fault,the more developed.The results show that the oil shale layers in the target formation in the study area has high gas generation potential and strong reformability,and the relatively developed structural fractures provide space for the accumulation and migration of oil and gas.The Oil-

关 键 词：油页岩 构造裂缝 主控因素 谭庄组 济源盆地 油气勘探 

分 类 号：P618[天文地球—矿床学] TE131[天文地球—地质学]