煤储层孔隙、裂隙系统研究进展

煤储层孔隙、裂隙系统由孔隙、微裂隙、内生裂隙和外生节理组成。煤相、煤阶、变质作用类型、构造作用和地下流体是影响煤储层孔隙、裂隙系统发育的关键因素。煤岩成分是煤储层孔隙、微裂隙、内生裂隙和外生节理发育的先决条件，而煤相控制煤的组成成分发育特征。煤阶及变质作用类型决定微裂隙和内生裂隙的发育程度。高温低压变质条件下形成的中高变质煤中，微裂隙和内生裂隙最发育。构造作用可以改造煤储层中的孔隙和微裂隙，但通常以影响煤储层中的外生节理发育最为明显。地下流体充填煤储层的孔隙、裂隙系统。其中地下稠性有机流体主要充填微裂隙和部分孔隙。岩浆气液挥发物在改造部分原有孔隙的同时，充填内生裂隙和部分微裂隙。含有无机沉积物的溶液主要充填外生节理和部分内生裂隙。

ADVANCES IN THE RESEARCH OF PORE-FRACTURE SYSTEM IN COAL RESERVOIR

Coal fades,coal rank and metamorphic type,structural Jointing or pressure,andthe fluids in coal reservoir are the key factors affecting Pore-fracture system develoPment incoal reservoir.The pore-fracture system consists of pore,microfracture,cleat and joint.The microfratures and cleats are especially developed in medium-low volatile bituminouswhich formed in the high temperature and low pressure metamorphism. Structural processing may alter the pore and microfracture somewhat,it evidently affects joints.he fluids incoal reservoir fill the pore-fracture system.The liquid and gas volatiles released from magmanot only reform some macerals and pore,but also fill some microfractures and cleat.Theliquids consist of inorganic sediments mainly fill joints and some cleats.