A Comparative Study on Fracture Characteristics of the Red Sandstone under Water and Nitrogen Gas Fracturing

Figure 8

Plots of volumetric strain and pressure with time during fracturing. (a) W1 loading rate: 0.09552 MPa/s. (b) G1 loading rate: 0.03259 MPa/s. (c) W2 loading rate: 0.07328 MPa/s. (d) G2 loading rate: 0.02254 MPa/s. (e) W3 loading rate: 0.06368 MPa/s. (f) G3 loading rate: 0.01237 MPa/s.

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(b)

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