Research and Application of Coal Seam Permeability Improvement Technology by Sectional Directional Hydraulic Fracturing

<div>Change of gas extraction effect in each borehole. (a) Variation curve of gas concentration in each borehole. (b) Gas concentration change in each borehole.</div>

Shock and Vibration

fig14

Figure 14

Figure 14: Research and Application of Coal Seam Permeability Improvement Technology by Sectional Directional Hydraulic Fracturing 