摘要：
以沁水盆地寿阳区块和柿庄区块为研究对象,揭示了不同构造应力强度作用下的地应力类型垂向转换机理及其对煤储层渗透率的控制作用.研究认为,构造应力强度决定地应力类型的垂向转化与否,而地应力类型的单一性或多样性是煤储层渗透率相对高低及其变化规律的决定性因素.在构造应力相对不活跃的寿阳区块,地应力类型单一,煤储层渗透率较高且随埋深和地应力增加呈单一指数递减的变化规律;在构造应力活跃的柿庄区块,出现地应力类型在垂向上的转换现象,三种地应力类型共存,煤储层渗透率较低且随埋深增加表现为分带指数递减规律.由于板块活动的影响,中国煤层气盆地承受较强的构造应力,但在不同盆地以及同一盆地内的不同构造位置,构造应力强度存在差异,地应力类型的单一性或多样性不同,煤储层渗透率随埋深变化规律也不同,区分各地区不同深度带所对应的地应力类型是研究煤储层渗透率变化规律的关键.%This paper focuses on Shouyang and Shizhuang coal bed methane (CBM) areas in Qinshui Basin,and aims to investigate the vertical transformation mechanism of the in-situ stress types under different tectonic stress intensities and the controlling effect on the permeability of the coal reservoir.The results show that tectonic stress intensity controls the vertical transformation of the in-situ stress types,but the single or diverse of in-situ stress type is the decisive factor of the relatively high and low permeability of coal reservoir.In the Shouyang CBM area where the tectonic stress is relatively inactive,there is a single type of in-situ stress,and the permeability of coal reservoir is high and decreases exponentially with the increase in buried depth and in-situ stress.In the Shizhuang CBM area,three types of in-situ stress coexist,the permeability of coal reservoir is low and shows zonal exponential decreases with increasing burial depth.Due to the influence of plate tectonics,the CBM basins in China bear strong tectonic stress,but there are differences in tectonic stress intensity in different basins and in different parts of the same basin,leading to different types of in-situ stress and variable permeability at different buried depths.Therefore,it is important to distinguish the in-situ stress types at different depths in order tounderstand the variations of permeability in coal reservoirs.
