Jia Tianrang, Yan Jiangwei, Liu Xiaolei, Feng Zhendong, Wei Guoying, Cao Liu
School of Safety Science and Engineering, Henan Polytechnic University, Jiaozuo, Henan 454003, China.
Collaborative Innovation Center of Coal Work Safety and Clean High Efficiency Utilization, Jiaozuo, Henan 454003, China.
ACS Omega. 2022 Mar 30;7(14):12296-12306. doi: 10.1021/acsomega.2c00782. eCollection 2022 Apr 12.
The correct understanding of the occurrence law of coalbed gas (CBG) is the premise of gas disaster prevention, outburst risk prediction, and gas exploitation. The factors affecting gas occurrence in different gas-geology units are different, so the correct division of gas-geology units is the foundation for studying the occurrence law of CBG. In view of this, this paper defined the division principle of gas-geology units. A gas-geology unit is an area with the same gas-geology characteristics. Based on the division of tectonic units, gas-geology units can be divided by integrating the differences of in situ stress, geological factors, and gas distribution of each tectonic unit. Then, taking the Guhanshan mine field in the Jiaozuo coalfield as an example, the analysis method of the occurrence law of CBG based on gas-geology units was expounded. Taking the EW section, NE section, and their extension lines of the Tuanxiang fault as the boundary, the Guhanshan mine field was divided into four tectonic units, and the factors affecting the gas occurrence of each tectonic unit were analyzed. Finally, according to the difference of the bedrock thickness and the CBG distribution in the four tectonic units, combined with the fracture development degree of the coal seam, surrounding rock, and the development degree of deformed coal, the Guhanshan mine field was divided into three gas-geology units, and their occurrence law of CBG was analyzed.
正确认识煤层气的赋存规律是进行瓦斯灾害防治、突出危险性预测及瓦斯开发利用的前提。不同瓦斯地质单元中影响瓦斯赋存的因素各异，因此正确划分瓦斯地质单元是研究煤层气赋存规律的基础。鉴于此，本文确定了瓦斯地质单元的划分原则。瓦斯地质单元是指具有相同瓦斯地质特征的区域。基于构造单元的划分，可通过综合各构造单元地应力、地质因素及瓦斯分布的差异来划分瓦斯地质单元。然后，以焦作煤田古汉山井田为例，阐述了基于瓦斯地质单元的煤层气赋存规律分析方法。以团香断层的东西向剖面、北东向剖面及其延长线为边界，将古汉山井田划分为四个构造单元，并分析了各构造单元影响瓦斯赋存的因素。最后，根据四个构造单元基岩厚度及煤层气分布的差异，结合煤层、围岩的裂隙发育程度以及构造煤发育程度，将古汉山井田划分为三个瓦斯地质单元，并分析了其煤层气赋存规律。
