【摘要】 煤中发育植物细胞残留孔隙、基质孔隙和次生孔隙，植物细胞残留孔隙主要为复杂孔隙树结构，有效孔隙率高。基质孔隙和次生孔隙主要为简单孔隙树结构，孔隙曲折度高，有效孔隙率低，煤基岩块中普遍发育宽１０～２０μｍ，高５０～１０００μｍ的微裂隙，大多数构成连结孔隙和内生裂隙及层面裂隙的重要通道。微裂隙的存在缩短了煤层甲烷扩散的距离，煤层甲烷除在微孔隙中扩散和内生裂隙中流动外，尚在微裂隙中扩散或流动。微裂隙的大小是决定煤层甲烷扩散或流动的关键。更多还原

【Abstract】 There are phyteral cell remaining pore ,matrix pore and new -forming pore in coal.The pores of remaining phyteral cell mainly are complicated dentritic structure,and the effective porosity is high.Matrix pore and new -forming pore mainly are simple dentritis structure,the pore tortuosity is high,and the effective porosity is low.There are microfractures in coal matrix block,which are 10-20μm wide,50-1000μm high.Many of microfractures link with the pore,cleat and bedding fracture.methane diffusion distance cuts down due to microfracture development.Besides flowing in the cleat and diffusing in the micropore,methane flows or diffuses in microfracture,depending on the size of the microfracture.更多还原