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

Figure 9

AE location on the fracture path under six different load methods. The yellow arrows refer to the crack growth in a wide region of kaolinite and illite, the green arrows refer to the crack growth in a small region of kaolinite and illite that was surrounded by quartz and feldspar, the blue arrows refer to the crack growth in the boundary of different minerals, and the black arrows refer to the crack growth in quartz and feldspar. 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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