School of Resources and Earth Science, China University of Mining and Technology MOE Key Lab of Coalbed
Methane Resources and Reservoiring Formation Process

基于沁水盆地南部潘庄区块主煤层的含气性特征,从煤阶、显微煤岩组分、构造、水文地质条件等4个方面探讨了影响该区块主煤层含气性的地质控制因素。结果表明:区块煤层含气性具有2个典型特征,太原组15号煤层含气性好于山西组3号煤层,与水力逸散作用对太原组煤层气保存条件破坏相对微弱的特点相关;含气饱和度随埋深加大呈现先减后增的变化,转折点埋深约500 m。同时发现,该区块随煤阶增高,含气量、孔隙度、吸附性均呈先升后降的变化,认为这是第4次煤化作用跃变对煤层气地质条件控制效应的具体体现;煤层含气量显现为次级向斜控气的典型特征。

Based on the gas-bearing property of main coal seams of Panzhuang Block in southern Qinshui Basin, the geological control factors such as coal rank, C oal maceral, geologic structures, and hydrogeological conditions, which have influence on the gas-bearing property, were discussed in the paper. The results showed th at the gas-bearing property of main coal seams had two typical characteristics: on the one hand, the gas-bearing property of No.15 coal seam of Taiyuan Formation wa s better than that of No. 3 coal seam of Shanxi Formation, which was closely related with the characteristics that the hydraulic migration-escape process relatively weak ly destroyed the CBM preservation conditions of Taiyuan Formation; on the other hand, with the burial depth increasing, the gas-bearing saturation increased first and t hen decreased, and the turning depth was around 500 meters. It was also found that with the coal rank heightening in this block, gas content, porosity and adsorption al | increase first and then decrease, which is considered to be the specific embodiment of the 4th coalification jump's control effect on CBM geological conditions. Meanw hile, the gas content displays typical characteristics of subsyncline-controlled CBM.

国家科技重大专项资助项目(2011ZX05034)；国家自然科学基金重点资助项目(40730422)；