Construction of geological guarantee system for green coal mining

Large-scale and high-intensity mining of coal resources has induced damage to geological conditions and ecological environment in coal mining areas. It is of great significance to study the coupling mechanism of geological structure-groundwater environment-ecological environment dynamic evolution caused by coal mining. Development of the theory and technology of geological guarantee for green coal development is also critical for ensuring the high-quality development of coal industry in China. In additional to the current coal mining technology, research status of geological guarantee for green development of coal is analyzed in this paper Scientific connotation of “system of geological guarantee for green development of coal” is proposed. Specifically, the following aspects are mainly included in the present study. (1) Comprehensive geological conditions for coal occurrence before mining, and the classification of ecological environment type of the mining area are evaluated and investigated. The damage type of the coal mining area and its main control factors are elaborated through the systematic investigation and analysis of 3D geological structure, hydrogeological conditions, geotechnical engineering properties and ecological environment. (2) Changes in geological conditions and functional system evolution of geological structures under the action of coal mining are studied. Deformation characteristics of overburden rocks and the response mode and damage law of geological conditions under coal mining conditions are clarified. The spatiotemporal evolution characteristics and damage mechanism of ecological environment under the coupling effects of stress field, deformation field, seepage field and other fields during mining are revealed. (3) Green geological guarantee technology and ecological environment functions after coal mining are reconstructed. The interaction among overburden rock structure, geological structure function and ecological environment after mining are studied. Utilization ways of gob and remaining resources are proposed, and functions of ecological environment in the coal mining area are recovered. A database containing the information on stratum structure, hydrogeological structure and mechanical properties of rock mass is created based on the accurate exploration and monitoring. A dynamic model of geological structure evolution during coal mining is established, and a comprehensive research platform for coal resource mining and geological environment protection in the ecologically-fragile areas is constructed, to provide support for green and safe development and ecological environment protection in the whole coal life cycle and further to seek the optimal way for solving the contradiction between coal mining and ecological civilization construction. In addition, the geological guarantee theory and technology for green coal mining with the multidisciplinary intersection of basic geology, mining science, ecology and humanist economics need to be developed in the geoscientific system of green coal mining from three scientific aspects, i.e., analysis, treatment and generalization. On this basis, the knowledge system of green and safe development integrating coal mining, geological engineering technology, ecological environment and humanistic economy need to be established to serve the green and safe coal mining.