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Full-Text Articles in Mining Engineering
Numerical Simulations And Wavefield Analysis Of In-Seam Wave Advance Detection In Viscoelastic Media, He Dixiu, Ji Guangzhong, Jiao Wenjie, Zhang Yawei, Yu Kun
Numerical Simulations And Wavefield Analysis Of In-Seam Wave Advance Detection In Viscoelastic Media, He Dixiu, Ji Guangzhong, Jiao Wenjie, Zhang Yawei, Yu Kun
Coal Geology & Exploration
In-seam waves are commonly applied to the advance detection of hidden faults in front of mining faces. However, coal seams, which have viscoelasticity actually, imposing absorptive and attenuation effects on in-seam waves. To investigate the wave field characteristics and propagation patterns of in-seam waves in viscoelastic coal seam media, this study built a three-dimensional geological model of coal measures with faults based on Kelvin-Voigt’s first-order velocity-stress equation. Using this equation, three-dimensional finite-difference numerical simulation was carried out. The results indicate that (1) for reflected in-seam waves in viscoelastic media, which exhibit high energy attenuation, their propagation and attenuation characteristics are …
Influence Of High In-Situ Stress Areas In The Coal Seam Roofs On Microseism-Based Tomographic Inversion, Liu Kaihang, Feng Lei, Yun Meihou, Cao Yunxing, Tian Lin
Influence Of High In-Situ Stress Areas In The Coal Seam Roofs On Microseism-Based Tomographic Inversion, Liu Kaihang, Feng Lei, Yun Meihou, Cao Yunxing, Tian Lin
Coal Geology & Exploration
High in-situ stress areas in the coal seam roofs are prone to induce mine dynamic hazard such as rock bursts. To meet the demand for safe coal mining, this study achieved real-time monitoring and swift early warning of high in situ stress areas. Specifically, based on data transmitted from microseismic stations in real time, this study conducted the inversion of the wave velocities in coal seams and rocks using a fast three-dimensional (3D) tomographic inversion algorithm. The accuracy of tomographic inversion results directly determines the judgment on the locations of high in situ stress areas. Therefore, by building a 3D …
Forward Modeling Of Amplitude Variation With Offset And Azimuth (Avoa) Response For Fracture Parameters Of Horizontal Transversely Isotropic Coal Seams, Wu Haibo, Liu Qinjie, Wang Jinchao, Li Zhi, Bai Ze, Xi Chaoqiang
Forward Modeling Of Amplitude Variation With Offset And Azimuth (Avoa) Response For Fracture Parameters Of Horizontal Transversely Isotropic Coal Seams, Wu Haibo, Liu Qinjie, Wang Jinchao, Li Zhi, Bai Ze, Xi Chaoqiang
Coal Geology & Exploration
Fractures serve as a key factor controlling the permeability of coal seams and play a crucial role in the exploration and exploitation of coalbed methane. This study focuses on the Amplitude Variation with offset and Azimuth (AVOA) response mechanisms of the fracture parameters of horizontal transversely isotropic (HTI) coal seams. To this end, this study calculated the equivalent elastic modulus of coal seams with vertical dry and fluid-saturated fractures using the Mori-Tanaka model and the Brown-Korringa anisotropic fluid substitution equation, respectively. Moreover, based on the petrophysical characterization of fractures in coal seams and the forward modeling using the HTI coal …