沁水盆地深煤层渗透率特征及其影响因素分析

Analysis on Permeability Characteristics and Influencing Factors of Deep Coal Seam in Qinshui Basin

渗透率是影响深部煤层开发的关键因素。本文立足沁水盆地南部,以柿庄区块为研究重点,通过分析深部煤层渗透率特征,探讨了影响深煤层渗透率的关键因素。研究发现煤储层渗透率随深度增大呈指数减小,且具明显分带性。深部煤储层渗透率变化的内在机理为地应力的转换,即浅部、中间及深部这三种应力状态的转换,导致渗透率呈指数减小。

Permeability is the key factor affecting the development of deep coal seam. Based on the southern Qinshui Basin and with Shizhuang block as the study key point,this paper analyzes the permeability characteristics of deep coal seam,and discusses the key factors affecting the permeability of deep coal seam. It is found that the permeability of coal reservoir decreases exponentially with the increase of depth and has obvious zoning. The internal mechanism of permeability change in deep coal reservoir is revealed,that is,the transformation of geo-stress. There are three geo-stress states in coal reservoirs: shallow stress state,intermediate stress state and deep stress state. The permeability decreases exponentially with the transition of the three stress states.