Numerical Modeling of Longwall-Induced Permeability Under Shallow Cover

Details

• Personal Author:
  Ajayi KM ; Gangrade V ; Khademian Z ; Schatzel, Steven J. ; Watkins E
• Description:
  Longwall-induced deformations could jeopardize the mechanical integrity of shale gas well casings positioned in the abutment pillar of a longwall mine. The in-situ and induced fracture networks surrounding the gas well could provide pathways for gas flow into the mine creating safety concerns. Hence, this study by the National Institute for Occupational Safety and Health (NIOSH) develops a Discrete Fracture Network (DFN) model to characterize the fractures in the overburden based on geomechanical analyses of mining-induced fracture apertures at a study site in Southwestern Pennsylvania. Multiple realizations of the stochastic DFN model that replicate potential fracture geometries are simulated, and the fracture permeability is compared with field measurements. The results show that the average permeabilities from the model agree closely with the field measurements. These findings provide critical information regarding fracture characteristics in the overburden, which will further be used to predict potential shale gas flow to the mine in the event of a casing breach for an unconventional gas well. [Description provided by NIOSH]
• Subjects:
  Mining Occupational Health Safety Ventilation
• Keywords:
  Gas Flow Geologic Models Longwall Mining Mathematical Models Mine Safety Mining Engineering Mining Industry
• Series:
  Mining Publications
• ISBN:
  9781032036793
• Publisher:
  CRC Press
• Document Type:
  Text
• Genre:
  Proceedings
• Place as Subject:
  OSHA Region 3 ; Pennsylvania
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  PMRD - Pittsburgh Mining Research Division
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  389-397
• NIOSHTIC Number:
  nn:20063604
• Citation:
  Mine Ventilation: Proceedings of the 18th North American Mine Ventilation Symposium (NAMVS 2021), June 12-17, 2021, Rapid City, South Dakota. Tukkaraja P ed. London: CRC Press, 2021 Jun; :389-397
• Editor(s):
  Tukkaraja P
• Federal Fiscal Year:
  2021
• NORA Priority Area:
  Mining
• Peer Reviewed:
  False
• Source Full Name:
  Mine Ventilation: Proceedings of the 18th North American Mine Ventilation Symposium (NAMVS 2021), June 12-17, 2021, Rapid City, South Dakota
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:1ed1381954e16f5772dc73198afbeac3c995302311f24cd129ac3e3fed8751a07f6b3d6fb129fe62679cf49681ee0367879070ffe516c977cdc066223f03a4d6
• Download URL:
  https://stacks.cdc.gov/view/cdc/215449/cdc_215449_DS1.pdf
• File Type:
  [PDF - 834.29 KB ]