枣庄八一矿瓦斯中H_2S气体异常成因分析

Genesis analyses of H_2S gas abnormity in gas of Bayi coal mine in Zaozhuang

通过对枣庄八一煤矿瓦斯中H2S异常区段地质背景、气体成分、浓度及H2S同位素分析,认为燕山晚期辉绿岩岩墙的热力作用使煤和围岩中含硫有机质和硫酸盐岩发生热化学分解作用和热化学还原作用,生成的H2S气体被岩墙两侧的煤层(瓦斯已遭逸散)吸附或充填于岩墙两侧煤层的孔、裂隙之中.岩墙东侧因断层和地下水的作用,煤层中H2S气体后期遭逸散,西侧因封盖条件较好而呈现出H2S气体异常.

Based on the analysis of the geological background, gas compositions and concentration of exceptional sector of H2S gas, and isotope, it is educed that H2S gas is derived from thermochemical decompesition effect of organic matter containing sulphur and thermochemical reducing action of sulfate in coal and adjacent formation in the effect of heat of diabase dike of the Late Yanshan movement, and that H2S gas is adsorbed by coals which located at the sides of the dike or infilled into pore-fracture of coals. Because of faults and ground water H2S gas of the coal seam of the east side of the dike is escaped in late stage, while the west side takes on H2S abnormity because of well capping conditions.