临兴地区深部煤储层煤体结构定量表征及影响因素分析  

Quantitative characterization and influencing factor analysis of coal structure of deep coal reservoirs in Linxing area

作　　者：高向东 周世豪 郭慧[2] 孙昊 张明达 骆潮威 王延斌[3] 吴翔[4] GAO Xiangdong;ZHOU Shihao;GUO Hui;SUN Hao;ZHANG Mingda;LUO Chaowei;WANG Yanbin;WU Xiang(School of Earth Science,East China University of Technology,Nanchang 330013,China;Development and Research Center,China Geological Survey,Beijing 100037,China;College of Geoscience and Surveying Engineering,China University of Mining and Technology,Beijing 100083,China;China United Coalbed Methane Corporation Limited,Beijing 100016,China)

机构地区：[1]东华理工大学地球科学学院,江西南昌330013 [2]中国地质调查局发展研究中心,北京100037 [3]中国矿业大学(北京)地球科学与测绘工程学院,北京100083 [4]中联煤层气有限责任公司,北京100016

出　　处：《煤炭科学技术》2024年第10期147-157,共11页Coal Science and Technology

基　　金：国家科技重大专项资助项目(2016ZX05066001-002);江西省研究生创新创业基金资助项目(YC2022-s595)。

摘　　要：煤体结构的定量表征是煤储层研究的热点问题之一。为精细刻画煤体结构的空间分布,查明其差异分布的主控因素,通过煤岩取心观测,借助地质强度因子对煤体结构进行定量表征,结合不同煤体结构的测井响应,构建了基于测井曲线的煤体结构量化表征模型,预测了煤体结构的空间分布,探讨了沉积、构造、地应力、微观力学性能对煤体结构的影响特征。研究结果表明:密度、伽马、声波、井径测井对煤体结构响应灵敏,利用测井多元回归法可以显著提高煤体结构的判识精度。研究区煤体结构以原生-碎裂结构为主,其次为碎裂结构,发育少量的原生结构和碎裂-碎粒结构。整个研究区的煤体结构分布可以归纳为四大类七个小分区。发育在潮道、砂坪、泥坪、三角洲平原、潟湖环境中的煤层,其厚度逐渐变大,但煤体结构与煤层厚度没有明显的关系。然而,灰分含量与煤体结构的完整性呈正相关,研究不同沉积环境中灰分的变化规律是揭示沉积环境对煤体结构控制特征的关键。煤储层变形程度越大,煤体结构越破碎。原生结构煤、原生-碎裂结构煤、碎裂结构煤的平均构造曲率分别为8.4×10^(-6)、18.7×10^(-6)、25.7×10^(-6)m^(-1)。断层发育区,煤体结构以碎裂结构为主。随着埋深增大,原位地应力增大,煤体结构完整性增强,地应力状态在此基础上进一步分化煤体结构。在浅部伸张-压缩过渡带以碎裂-碎粒结构为主;在深部压缩状态以原生-碎裂结构为主;在深部压缩-伸张过渡带碎裂结构的比例有所增加。煤岩微观力学性能受控于煤基质组分和显微孔隙结构。煤岩无机组分力学强度高于有机组分,且无机组分孔隙孔径比有机组分孔隙孔径小,则无机组分含量越高,煤岩力学强度越高,煤体结构越完整。该研究成果为煤层钻井施工、压裂改造、储层评价提供参考。The quantitative characterization of coal structure is one of the hot topics in coal reservoir research.To finely characterize the spatial distribution of coal structure and identify the main controlling factors for its differential distribution,through observation and measurement of coal cores,quantitative characterization of coal structure using geological intensity factors,and statistics of logging response of different coal structures,a quantitative characterization model of coal structure based on logging curves was constructed.The spatial distri-bution of coal structure was predicted,and the influence characteristics of sedimentation,structure,in-situ stress,and micro-mechanical properties on coal structure were explored.The research results indicate that density,gamma-ray,interval transit time,and caliper loggings are sensitive to the coal structure,and the use of logging multiple regression method can significantly improve the accuracy of coal structure identification.The coals in the study area are mainly composed of primary-fragmented coals,followed by cataclastic coals,with a small amount of primary and cataclastic-granulated coals developed.The coal structure of the entire study area can be divided into four categories and seven small areas.The sedimentary environment can affect the coal structure by controlling the thickness of coal seam development.The thickness of coal seams developed in tidal channels,sand flats,mud flats,delta plains,and lagoon environments gradually increases,but there is no obvious relationship between coal structure and coal seam thickness.However,the ash content is positively correlated with the integrity of coal structure,and studying the changes in ash content in different sedimentary environments is the key to revealing the control characteristics of sedimentary environments on coal structure.The average structural curvature of primary structured coals,primary-fragmented structured coals,and cataclastic coals are 8.4×10−6,18.7×10−6,25.7×10−6 m−1,respectively.Whe

关 键 词：鄂尔多斯盆地 临兴地区 深部煤储层 煤体结构 定量表征 

分 类 号：TD15[矿业工程—矿山地质测量] P584[天文地球—岩石学]