Assessment of factors and mechanism contributing to groundwater depressurisation due to longwall mining
M.Chen1
C.Zhang1
I.Canbulat1
S.Saydam1
G.Fan2
D.Zhang3
1.School of Minerals and Energy Resources Engineering,University of New South Wales,Sydney,Australia2.School of Mines,China University of Mining & Technology Xuzhou,China3.State Key Laboratory of Coal Resources and Mine Safety,Xuzhou,China
摘要：Assessment of mining impact on groundwater is one of critical considerations for longwall extension and sustainability,how-ever usually constrained by limited data availability,hydrogeological variation,and the complex coupled hydro-mechanical behaviour.This paper aims to determine the factors and mechanism of groundwater depressurisation and identify knowledge gaps and methodological limitations for improving groundwater impact assessment.Analysis of dewatering cases in Aus-tralian,Chinese,and US coalfields demonstrates that piezometric drawdown can further lead to surface hydrology degrada-tion,while the hydraulic responses vary with longwall parameters and geological conditions.Statistical interpretation of 422 height of fracturing datasets indicates that the groundwater impact positively correlates to panel geometry and depth of cover,and more pronounced in panel interaction and top coal caving cases.In situ stress,rock competency,clay mineral infillings,fault,valley topography,and surface-subsurface water interaction are geological and hydrogeological factors influencing groundwater hydraulics and long-term recovery.The dewatering mechanism involves permeability enhance-ment and extensive flow through fracture networks,where interconnected fractures provide steep hydraulic gradients and smooth flow pathways draining the overlying water to goaf of lower heads.Future research should improve fracture network identification and interconnectivity quantification,accompanied by description of fluid flow dynamics in the high fracture frequency and large fracture aperture context.The paper recommends a research framework to address the knowledge gaps with continuous data collection and field-scale numerical modelling as key technical support.The paper consolidates the understanding of longwall mining impacting mine hydrology and provides viewpoints that facilitate an improved assessment of groundwater depressurisation.
机标关键词：mechanismsatieprespressrisaisattionassessment
论文发表日期：2024-08-28
在线出版日期：2025-08-15（本平台首次上网日期，不代表文献的发表时间）
页数：36( 238-273 )
英文信息