Research On In-situ Stress Distribution In Wugou Mine Based On 3D Seismic And Simulation

The tectonically complex coal mine has dense fault development,complex geological conditions and high potential for mine power hazards,and the safe and efficient production of the coal mine is facing great challenges.In this study,3D seismic data and logging data are used as data sources to construct a high-precision 3D geological model and geomechanical model,finite element simulation to simulate the ground stress field in the mining area,identify the distribution areas of ground stress anomalies in the main mining seam in the mining area,analyse the characteristics of ground stress distribution and the main influencing factors,and provide key data support for the transparent and unmanned production of coal mines and the prevention and control of power hazards.The 3D seismic data,logging data and geological data of the mining area were integrated,and the 3D seismic data were interpreted interactively and with seismic attribute technology to construct a 3D geological model.Firstly,all the boreholes in the mining area are synthesised with seismic records,and the kinematic and kinetic characteristics of the reflected waves of the main mining seam on the seismic profile are combined to identify the corresponding seam level of the main mining seam and carry out seam tracing.Secondly,combined with the interactive interpretation of seismic profiles and seismic attribute interpretation,the various geological formations such as faults developed in the mining area are finely interpreted,and the intersection between coal seams and various geological formations is clarified.Finally,using the stacked acceleration generated during the seismic data processing as data input,combined with the DIX formula and logging constraints,the high-precision layer velocity field in the mining area is constructed,and the high-precision time-depth conversion of the main coal seams and major geological bodies in the mining area is realised,and a 3D geological model of the mining area depth domain is constructed.The 3D geological model and logging results are integrated,and finite element simulation is used to study the distribution of ground stress in the mining area and the main factors influencing the distribution of ground stress anomalies.Firstly,based on the logging information and empirical formulae,the mechanical parameters of each rock group in the geological model are calculated in sections to construct a 3D geomechanical model of the mining area.Secondly,a finite element simulation model was constructed on the basis of the geomechanical model by selecting a suitable grid segmentation method and key parameters.Thirdly,based on the background of the ground stress field in the study area and the correlation between the ground stress and the burial depth in the mining area,the boundary conditions of the finite element model were set and the distribution of the ground stress field in the mining area was simulated.Finally,the stress distribution pattern of key coal seams in the mining area was analysed in conjunction with the stress coefficient,Mises stress and other indicators,and the influence of faults on the abnormal distribution of ground stress in the mining area was investigated.The results show that the maximum horizontal principal stress,minimum horizontal principal stress and vertical principal stress in the study area and the target coal seam are mainly controlled by the burial depth,and the greater the burial depth,the higher the stress value;the distribution pattern of the stress coefficient is opposite to the burial depth,and generally shows a negative correlation with the burial depth,and the stress coefficient gradually decreases and converges to a constant as the burial depth increases;obvious stress concentration can be found in the two-dimensional stress profile and the stress cloud map of the coal seam.The spatial correlation model and Monte Carlo stochastic simulation results show that the high stress areas are directly related to the fault distribution,and the radius of correlation between the two is between 75-125 m.In summary,the method proposed in this thesis is feasible and practically effective in predicting the ground stress field in complex mining areas based on 3D seismic 3D geological modelling and ground stress simulation,which can provide useful reference for the prevention and control of dynamic disasters such as impact ground pressure and coal and gas protrusion.There are 91 figures,14 tables,and 118 references in this thesis.