鄂东缘临兴地区深层煤层顶底板与含气性耦合关系研究  

Study on the coupling between the hanging-and foot-wall beds and the gas content of deep coal seams in the Linxing area,eastern margin of the Ordos Basin

作　　者：霍少伟 冯兴强 吴见[3,4] 张守仁 周磊[2] 钱竹良 晁巍巍 HUO Shaowei;FENG Xingqiang;WU Jian;ZHANG Shouren;ZHOU Lei;QIAN Zhuliang;CHAO Weiwei(College of Resource and Environment,Yangtze University,Wuhan 430100,Hubei,China;Institute of Geomechanics,Chinese Academy of Geological Sciences,Beijing 100081,China;China United Coalbed Methane Corporation Ltd,Beijing 100011,China;Provincial Center of Technology Innovation for Coal Measure Gas Co-production,Taiyuan 030000,Shanxi,China;Geophysical Prospecting Research Institute of Jiangsu Oilfield Company,Sinopec,Nanjing 210046,Jiangsu,China)

机构地区：[1]长江大学资源与环境学院,湖北武汉430100 [2]中国地质科学院地质力学研究所,北京100081 [3]中联煤层气有限责任公司,北京100011 [4]三气共采省技术创新中心,山西太原030000 [5]中国石油化工股份有限公司江苏油田分公司物探研究院,江苏南京210046

出　　处：《地质力学学报》2025年第2期235-247,共13页Journal of Geomechanics

基　　金：中国地质调查局地质调查项目(DD20242777);国家自然科学基金项目(42172176)。

摘　　要：鄂尔多斯盆地东缘临兴地区的深层煤层气有巨大的勘探开发潜力,已经成为重点勘探开发区。研究表明煤层顶底板对煤层气的富集保存有重要作用,但目前尚未开展深层煤层顶底板对含气性影响的系统研究,二者的耦合关系不清楚。为丰富深层煤层气富集理论,综合应用测井、钻井和录井等资料,针对临兴地区8+9号煤层顶底板特征与含气性的耦合关系展开了研究。研究结果发现,临兴地区本溪组—太原组发育障壁-潮坪-潟湖沉积体系,8+9号煤层主要发育于潮上带、泥炭坪和泥炭沼泽,顶底板沉积环境为泥坪、潟湖、灰坪和砂坪沉积微相。受沉积环境的影响顶底板主要由灰岩、泥岩和砂岩3种岩性构成;煤层顶板和底板厚度平面分布变化较大,顶板厚度介于1.90~19.00 m,底板厚度介于1.99~21.19 m;具有顶灰底泥型、顶泥底灰型、顶泥底泥型、顶泥底砂型、顶砂底灰型、顶砂底泥型、顶砂底砂型7种不同的顶底板岩性组合。进一步研究顶底板特征与煤层含气量的关系发现,顶灰底泥型、顶泥底灰型和顶泥底泥型煤层呈现出高含气量的特征;顶泥底砂型和顶砂底灰型煤层呈现较高含气量的特征;顶砂底泥型和顶砂底砂型煤层呈现低含气量的特征;同一岩性下,顶底板厚度越大,煤层含气量越高,顶底板厚度与含气量呈正相关。利用层次分析法可划分为3类深层煤层顶底板与含气性的耦合模式:Ⅰ类(耦合关系好)含气量大于15 m^(3)/t、Ⅱ类(耦合关系较好)含气量范围为12~15 m^(3)/t、Ⅲ类(耦合关系差)含气量小于12 m^(3)/t。该研究成果明确了深层煤层顶底板对含气量的控制作用,对深层煤层气的有利区评价、优选和开采具有重要的指导意义,并进一步丰富了深层煤层气富集理论。[Objective]The deep coalbed methane in the Linxing area at the eastern margin of the Ordos Basin has great potential for exploration and development and has become a key exploration and development target.Research shows that the hanging-and foot-wall beds of the coal seams play an important role in the enrichment and preservation of coalbed methane.At present,there is lack of systematic research on the influence of the hanging-and foot-wall beds of deep coal seams on the gas content,and the coupling between them is not clear.This study aims to extend the theory of methane enrichment in deep coal beds.[Method]Through the comprehensive application of logging,drilling,and mud logging data and the use of the Analytic Hierarchy Process(AHP),the coupling between the characteristics of the hanging-and foot-wall beds of the No.8+9 coal seam and its gas-bearing property were studied.[Results]The research results are as follows:(1)In the Linxing area,the Benxi Formation–Taiyuan Formation developed in a barrier-tidal flat-lagoon sedimentary system.The No.8+9 coal seam mainly developed in the supratidal zone,peat flat,and peat swamp,and the sedimentary environments of the hanging-and foot-wall beds are sedimentary microfacies such as mud flat,lagoon,ash flat,and sand flat.(2)Influenced by the sedimentary environments,the hanging-and foot-wall beds are mainly composed of three lithologies,namely limestone,mudstone,and sandstone.The thicknesses of the hanging-and foot-wall beds of the coal seam vary greatly along the lateral extent.The thickness of the hanging-wall bed ranges from 1.90 to 19.00 m,and the thickness of the foot-wall bed ranges from 1.99 to 21.19 m.There are seven different lithological combinations of the hanging-and foot-wall beds,including top-limestone bottom-mud,top-mud bottom-limestone,top-mud bottom-mud,topmud bottom-sand,top-sand bottom-limestone,top-sand bottom-mud,and top-sand bottom-sand.(3)Further research on the relationship between the characteristics of the hanging-and foot-wall and the gas conte

关 键 词：深层煤层气 顶底板 含气性 耦合关系 层次分析法 鄂尔多斯盆地东缘 

分 类 号：P618.13[天文地球—矿床学]