开平向斜两翼瓦斯赋存差异性分析

Difference Analysis of Gas Occurrence in Kaiping Syncline Wings

针对处于同一构造单元,分属于开平向斜两翼的矿井,瓦斯赋存状况截然不同的情况,利用构造剖面分析、断层统计分析、地下水动力分析等从地质构造和水文地质条件方面揭示了瓦斯赋存差异性的根本原因。结果表明:不对称向斜控气构造,倾角直立、甚至倒转翼挤压性逆断层发育,煤层瓦斯封盖条件得以加强,煤层含气性远好于倾角平缓翼;"水大瓦斯小"是瓦斯地质的一条基本规律;煤层瓦斯与地下水流动的方向相同,就会形成相对瓦斯贫乏区。以开平向斜轴部为界,东南翼和西北翼地质构造和水文地质条件等方面存在较大差异,导致矿井瓦斯赋存具有各自的特征和分布规律。

Aiming at the situation of difterent gas occurrence status in a mine which belongs to Kaiping syncline wings in the same tec- tonic unit, profile analysis, fault analysis, groundwater dynamic analysis are used to reveal the root causes of gas occurrence difference from the aspects of geological structure and hydrogeological condition. The results show that asymmetric syncline controlled gas struc- ture, angle upright, even reverse wing compressional reverse faults growth, gas sealing conditions of coal seam can be strengthened, coalbed methane content is far better than the gentle dip angle wing; ＂larege water and little gas＂ is a basic law of gas geology; gas and groundwater flowing in the same direction of coal seam will form the relatively poor gas area. Taking Kaiping syncline axis as the bound- ary, there are great differences in the southeast wing and northwest wing of geological structure and hydrogeological condition, which re- suits in different characteristics and distribution laws of mine gas occurrence.