Study and application of the influence of inclination angle on the cross-fusion mechanism of high gas thick coal seam

Abstract

In this study, to better decide the effect of coal seam dip angle upon the dynamic change of the cross-fusion in gas transport and storage areas during the progress of working face in the high gas thick coal seam, a two-dimensional physical simulation experiment regarded as the theoretical research was conducted to properly explore the variation law of overburden fracture. The results demonstrated that the boundary of the gas transport zone was located in the region of fracture separation. The boundary of the gas storage area was located in the abrupt penetration zone. Also, according to the information theory, the state of the gas transport and storage areas was determined by the changing trend of the fracture rate and fracture entropy. The mathematical representation model of the dip effect in gas transport and storage areas was established. The criteria upon which the regional location of the gas transport area and gas storage area can be based were put forward. The cross-fusion evolution process of the dip effect in gas transport and storage areas was revealed as well. The research results could provide guidance for realising directional and accurate gas extraction.

Keywords

Coal seam dip angle / Cross fusion / High gas thick coal seam / Overburden fracture / Gas transport and storage areas

Acknowledgements

This research was financially supported by the National Natural Science Foundation of China (No. 5217-4205); Shaanxi Provincial Outstanding Youth Science Fund Project (No. 2023-JC-JQ-40); National Key Research and Development Project (No. 2023YFC3009004); Key Project of Shaanxi Provincial Department of Education (No. 22JY040); Xinjiang Uygur Autonomous Region Key Research and Development Task Special Project (No. 2022B01034-3); Key Laboratory of Green Coal Mining in Xinjiang, Ministry of Education (No. KLXGY-KA2404); and Shaanxi Provincial Key Research and Development Task General Project (No. 2024GX-YBXM-490). The authors are indebted to the coal mines that provided the coal samples used in this study.

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