Because of faults and ground water H_2S gas of the coal seam of the east side of the dike is escaped in late stage,while the west side takes on H_2S abnormity because of well capping conditions.

• 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.