A 2-D differential-stress-based analysis on the tendency of mining-induced fault reactivation

Fault reactivation related geological disasters such as mine seismicity, ground subsidence, water inrush and gas outburst seriously affect mine production and miner's safety, developing a practical analytical method for the risk assessment of mining-induced fault reactivation is of great significance for underground mining safety. In this study a 2-D systematic procedure for a rapid tendency analysis of mining-induced fault reactivation is developed. It is an analytical procedure developed on the basis of the mining-induced differential stress and of the relationship between the differential stress and the corresponding critical reactivation angles, in this work we proposed to use the following three conditions to assess the tendency of mining-induced fault reactivation: (1) whether the fault angle closes to the optimum angle of reactivation; (2) whether the mining-induced differential stress reached the minimum triggering differential stress required for fault reactivation; (3) if the second condition is satisfied then evaluating whether the fault angle is within the range of the two corresponding critical reactivation angles. The assessment procedure proposed in this study is practical and it can provide a significant reference for mining engineers to better understand the mining-induced fault reactivation and to better assess the risk of fault reactivation related geological disasters.