Uncovering the Fracture Mechanism of Overburden Aquifers in Mining Areas

Strategic Insights -

A recent study published in Applied Sciences has provided new insights into the fracture mechanism of overburden aquifers during mining under anticlinal structural zones in western mining areas. The research, conducted by China University of Mining and Technology, reveals the primary causes of water inrush-induced support failures in working face 1309 of the Guojiahe Coal Mine. The study demonstrates that the large slope angle of the anticlinal zone and significant elevation difference between slope initiation points and the axis are the primary causes of water inrush-induced support failures.

Key Takeaways:

  • The conglomerate of the Yijun Formation serves as the critical aquifer responsible for water inrush, while the coarse sandstone in the Anding Formation acts as the key aquiclude.
  • Overburden fractures and maximum bed separation zones during rise mining predominantly develop toward the goaf side, influenced by the slope angle.
  • The height of the collapse zone of the working face is 65 m, and the distribution of broken rock blocks in the collapse zone is disordered.
  • The key aquiclude's fracture triggers synchronous collapse of overlying strata, generating the most extensive and rapidly developing fracture networks.
  • The fracture surface on the mining face side and the overlying strata separation zone jointly form a 'saddle-shaped' high-porosity area, whose distribution range shows a positive correlation with the working face advance distance.
  • The porosity variation in the key aquiclude undergoes three distinct phases with advancing distance: first remaining stable, then increasing, and finally decreasing, with porosity reaching its peak when the key stratum fractures upon attaining its ultimate caving interval.

Statistics:

  • The research was supported by the National Natural Science Foundation of China and the Postgraduate Research & Practice Innovation Program of Jiangsu Province.
  • The study examining the characteristics of overlying rock breakage and fissure evolution in the mining of extra-thick coal seams in anticline structural area was published in Applied Sciences, Vol. 15, No. 16 (2025).
  • The height of the collapse zone of the working face is 65 m.
  • The fractured area of the key aquiclude reached its peak when the key stratum fractures upon attaining its ultimate caving interval.

Sources:

  • China University of Mining and Technology
  • Jun Wang, State Key Laboratory for Fine Exploration and Intelligent Development of Coal Resources, China University of Mining and Technology, Xuzhou 221116, People's Republic of China
  • Shibao Liu, Xin Yu, Haoyuan Gu, Huaidong Liu, Changyou Liu, Applied Sciences, Vol. 15, No. 16 (2025)
  • National Natural Science Foundation of China
  • Postgraduate Research & Practice Innovation Program of Jiangsu Province
  • Applied Sciences, Vol. 15, No. 16 (2025), (https://doi-org.sdpl.idm.oclc.org/10.3390/app15168812)