Study on failure mechanism of tight sandstone based on moment tensor inversion

Understanding deep rocks' mechanical properties and failure evolution is crucial for efficient resource development. This study investigates the of tight sandstone analyzes its acoustic emission (AE) characteristics using a combined discrete element model moment tensor inversion. The AE activity during loading categorized into three stages: crack initiation, stable propagation, unstable propagation. Confining pressure suppresses initiation stage due to damage healing phenomenon. Moment inversion reveals that tensile primary source, despite samples exhibiting splitting shear modes. proportion types varies with stress levels depends on environment. Microcracks initiate at ends sample propagate inward along direction, resulting in blank area events middle. can be utilized predict specimen mode. b value, representing ratio small large magnitude events, decreases increase confining pressure, indicating higher energy release under high pressure. research results provide reference predicting sandstone.