Coal mining leads directly to changes in geophysical rock formations and upsets the equilibrium of gas concentrations in gas–liquid channels, which can cause mining disasters. In this study, based on the fractal dimension theory, the influence of coal thickness on gas migration channels in geophysical rock formations under fully mechanized mining faces was analyzed. The results demonstrated that channel boundaries become mutated in overburden. The increase in coal seam thickness affects directly the height of the gas migration channel. Under the condition of a 6 m mining height, the height of the gas migration channels developed to 60 m and the width reached 33 m. At the same time, the fractal dimension under the condition of 6 m mining height increased by 1.07 and 1.23 times compared with 4 m and 2 m. The results further indicated that optimal analyses and adjustment based upon coal thickness to determine high-level borehole arrangements can ensure safety in completing mining activities at the working face. The results provided practical and theoretical foundations for identifying high-concentration gas zones in geophysical rock formations and may serve as a feasible reference for further reducing the occurrence of geological and gas-related disasters.

煤炭开采直接导致地球物理岩层的变化，破坏气液通道内瓦斯浓度的平衡，从而引发矿难。本研究基于分形维数理论，分析了煤层厚度对综采工作面地球物理岩层瓦斯运移通道的影响。结果表明，河道边界在覆盖层中发生了突变。煤层厚度的增加直接影响瓦斯运移通道的高度。在开采高度6 m的情况下，瓦斯运移通道高度发育至60 m，宽度达到33 m。同时，6 m采高条件下的分形维数较4 m和2 m增加了1.07和1.23倍。研究结果进一步表明，根据煤厚进行优化分析和调整，确定高位钻孔布置，可以确保工作面安全完成采矿活动。研究结果为地球物理岩层中高浓度瓦斯区识别提供了实践和理论依据，可为进一步减少地质灾害和瓦斯灾害的发生提供可行的参考。