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

Figure 6

Continuous growth and deflection of cracks (in red) under six different loading methods. The yellow arrows refer to crack growth in large scales of kaolinite and illite, the green arrows refer to crack growth in smaller scales of kaolinite and illite surrounded by quartz and feldspar, the blue arrows show crack growth in the boundary between different minerals, and the black arrows refer to crack growth in quartz and feldspar.

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