天然气工业2026，Vol.46Issue(5)：11-24,14.DOI:10.3787/j.issn.1000-0976.2026.05.002
鄂尔多斯盆地煤岩气储层孔裂隙结构类型划分及其勘探意义
Classification of pore-fracture structures in coal-rock gas reservoirs in the Ordos Basin and its exploration significance
摘要
Abstract
The Ordos Basin harbors immense resource potential of coal-rock gas.At present,however,there is a lack of thorough research on the maceral characteristics,pore classification,pore structure characterization,and controlling mechanisms on gas occurrence in coal-rock gas reservoirs.Taking the deep coal reservoirs of Carboniferous Benxi Formation in the Ordos Basin as the research object,this paper systematically develops a set of full-scale quantitative characterization method for the pore-fracture structures in coal-rock gas reservoirs by means of various experimental methods such as coal petrographic and quality analysis,scanning electron microscopy(SEM),Nano-scale CT scanning and 3D reconstruction,gas adsorption,and high-pressure mercury intrusion(HPMI).In addition,the types,distribution characteristics and controlling factors of the microscopic pore-fracture structures are systematically revealed,and the pore-fracture structures in coal-rock gas reservoirs are classified into three types.The following results are obtained.First,the Benxi Formation coal reservoirs are mainly composed of bright and semi-bright coals with medium to high evolution degree,where primary structures are dominant,and pore-fracture structures are dominated by organic matter pores and cellular pores.Second,the pore size distribution in the Benxi Formation coal reservoirs is primarily micropores(65.0%of total pore volume),followed by microfractures(25.4%of total pore volume),with macropores and mesopores underdeveloped,overall presenting the characteristics of dual pore-fracture structures.Third,the pore-fracture structures are jointly controlled by metamorphism degree,vitrinite content,and ash yield.The northern part of the study area is generally dominated by the"U"-shaped bimodal-microfracture predominance type;the central part mainly develops the"U"-shaped bimodal-micropore and microfracture predominance type,which has the greatest exploration and development potential;and the southern part is mainly characterized by the"U"-shaped bimodal-micropore predominance type.Fourth,the exploration potential and fracture network demand for development and production of coal-rock gas are controlled by pore-fracture structure types and total gas content.In conclusion,this study provides important guidance for the exploration direction and sweet spot prediction of coal-rock gas in the Ordos Basin.关键词
煤岩气/孔裂隙特征/含气性/控制因素/石炭系本溪组/煤岩气赋存Key words
Coal-rock gas/Pore-fracture characteristics/Gas content/Controlling factor/Carboniferous Benxi Formation/Occurrence of coal-rock gas分类
能源科技引用本文复制引用
侯雨庭,刘翰林,李亚男,邓泽,费世祥,范立勇,黄道军,周国晓,史云鹤,王怀厂,虎建玲,张城玮..鄂尔多斯盆地煤岩气储层孔裂隙结构类型划分及其勘探意义[J].天然气工业,2026,46(5):11-24,14.基金项目
新型油气勘探开发国家科技重大专项"深层煤岩气成藏机理与效益开发技术"(编号:2025ZD1404200)、中国石油科技项目"煤岩气富集规律与开发机理研究"(编号:2024DJ23). （编号:2025ZD1404200）
