Comparative Study on Mineral-Scale Microcrack Propagation of Shale under Different Loading Methods

Figure 10

The initiation of small-scale en echelon intermittent fractures under six different load methods. Red dots are the AE location of tensile fractures, purple dots are the AE location of shear fractures, and the colors between the two are the AE location of tensile-shear fractures. The size of the dot represents the level of AE energy.

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