Research Article
Hydraulic Fracture Propagation and Permeability Evolution in the Composite Thin Coal Seam
Figure 3
Pore pressures and hydraulic fracture (microcrack-band) geometries at different injection pressures.
(a) Fluid-injection pressure: 3 MPa |
(b) Fluid-injection pressure: 5.4 MPa |
(c) Fluid-injection pressure: 8.2 MPa |
(d) Fluid-injection pressure: 8.2 MPa (continuous injection of fluid) |