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

Figure 11

The AE location when the second large-scale en echelon intermittent fractures were formed under six different loading methods. The red arrows refer to the strong mineral aggregate. 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.

(a)

(b)

(c)

(d)

(e)

(f)