## 5 Discussion  
Geological structures, especially faults, are very important for the stability control of the roadway, and faults are often seen in mine production. The fault dip distribution in the Pulang copper mine is generally steep, about 60\({}^{\circ}\) to 85\({}^{\circ}\), and the thickness is between 0.1 m and 2 m. During the construction of the bottom structure out of the mine through the vein, several roadways inevitably pass directly through the fault. Therefore, the control and monitoring of the faults is of high significance for the safety of the mining activities, and some studies have previously been conducted to investigate the activation properties of faults. Three-dimensional numerical simulations were used by [PERSON] (2016) to study the stress evolution characteristics and the activation law of mining reverse faults under hard and thick layers, to establish a fault model and to derive the stress evolution characteristics of over-reverse faults by mining activities. To investigate the influencing factors and critical water pressure leading to the rupture of hydraulic conductivity faults, a simplified fracture mechanics model was used by [PERSON] (2016) to study the sudden water accidents caused by underground hidden faults. Although these approaches achieved effective results, they were only at the model level for fault activation, and there was no real-time monitoring of the suddenness and variability of the disasters caused by fault activation. With the application of microseismic technology in coal mining, microseismic monitoring techniques were used by [PERSON] and [PERSON] (2016, 2017) and others to achieve real-time monitoring of the activation performance of faults; however, the monitoring data were less processed; so, their monitoring was not an early warning system.  
From the results of the above study and analysis, it can be seen that the distribution pattern of the microseismic events and the distribution of the apparent volume and energy density with time were predictive for the anomalous results due to fault activation and also provided a basis for the researchers to study the microseismic response studies at the faults; the predictions were consistent with the actual results. The mine activity led to the activation of faults, which in turn led to an increase in the number of microseisms, and as the apparent volume density increased, the the apparent bulk density increased, the energy density continued to accumulate, and the risk factor gradually increased, resulting in tunnel crushing and deformation. When the energy density index suddenly becomes small, mining disasters such as rockbursts and massive rock rupture can occur, and the difference in the timing of the apparent bulk density and energy index makes it possible to make predictions by calculating the bulk density before the sudden changes in energy density, which greatly improves the predictability of rock bursts and coal mine production, safety. The real-time monitoring of the Pulang copper mine is more relevant and timely than the monitoring of ordinary fault models, and this is more statistically significant, predictive, and instructive for the way ordinary monitoring data can be processed.  
Figure 10: Roadway crushing and deformation in the corresponding area at the 3736 m level. The red lines depict the fissures due to ground pressure activity.