Figure 4
From: Research on instability characteristics and precursory effect of coal-rock parting-coal structures
Locations of AE sources during slip, fracture, and instability of the four compound samples. Note: The color of the AE sources denotes energy release (green: 0–10 ms·mV; blue: 10–102 ms·mV; yellow: 102–103 ms·mV; red: 103–104 ms·mV), and the AE energy is time integral of the absolute signal voltage.
