Seismic timelapse monitoring of gas drainage in an underground coal ...
WEBMar 15, 2021 · During the later coal recovery, we measured the loions and thicknesses of mylonitic coal in the working face day after day, and found a thick mylonitic coal zone (– m thick) developed between the two boreholes that produced the highest coal powder (Fig. 2). As the loions and thicknesses were measured directly, the zone has ...