Geological guarantee of coal green mining

Constrained by the characteristics of energy resource endowment of “lack of oil,less gas and relatively rich coal”,coal is always the basic guarantee of energy security in China. Coal resource is a layered sedimentary mineral formed in the process of earth evolution,and it is a part of the near surface crust. Coal mining will cause damage to geological conditions and ecological environment. The geological guarantee of coal green mining is based on the geolog- ical conditions of coal resources occurrence,which provides the geological theory and technical support for the safe and efficient mining of coal resources,mitigating and reducing the damage to the geological conditions and ecological envi- ronment of the mining areas. This paper systematically explains the geological guarantee theory and technology for green coal mining from four aspects:connotation,scientific issues,technical issues and research ideas. The geological guarantee of green coal mining highlights the change of geological conditions under the disturbance of deep coal min- ing,emphasizes the overall study of coal mining activities,geological structure and the change of surface ecological en- vironment,and focuses on the change of geological con-ditions and the evolution of ecological environment in the cate- gory of space-time effect caused by underground mining operations. The general research idea is to explore finely be- fore mining,reduce damage effectively during mining and restore utilization after mining. Before mining,the fine explo- ration of the integration of space,sky and earth is carried out to find out the spatial occurrence characteristics of coal bearing mineral resources and the main geological factors to maintain the surface ecosystem,and to build a high-preci- sion three-dimensional model covering coal bearing resources,geological conditions,ecological environment and other elements,so as to evaluate the best utilization direction of coal resources and regional environmental carrying capacity. During mining,the damage detection and monitoring of geological conditions are carried out to reveal the variation laws of stress field,deformation field and seepage field,to study the characteristics of coal bearing gas and groundwater mi- gration and gushing,to analyze the geological factors leading to the occurrence of surrounding rock dynamic disasters, and to put forward the advance warning theory and prevention and control measures of coal and gas outburst,water hazard,bumping pressure and other disasters. After mining,the water body,harmful gas and residual resources in the goafs shall be detected,and the deformation characteristics of the surrounding rock and coal pillar of the roadway shall be monitored. The interaction of coal rock water and the stability change of goafs are studied,the geological conditions and the evolution process of surface ecological restoration are studied,and the comprehensive utilization theory and technology of underground space and residual resources are put forward. The green mining geological guarantee covers the whole process of coal search,exploration,mining and utilization of goafs,and pursues the coordinated development of coal bearing mineral resources and ecological environment protection.