Location and mechanism analysis of curtain water inrush channels based on MTI-derived parameters-a case study

•Analysis method for mining-induced fracture, damage and stress state was developed.•A new calibration method for the curtain water inrush channel was developed.•The work provides a new feasible idea for the curtain water inrush analysis. A grout curtain's stability and water-plugging effect are directly related to the safe production of water-rich mines. The progressive damage to the surrounding rocks of the grout curtain under mining disturbance may induce the development and coalescence of fractures and the failure of the grout curtain, further causing the formation of water inrush channels and triggering water inrush disasters. Understanding the mechanisms behind the formation and evolution of water inrush channels is inherently challenging in theory, thus necessitating field monitoring methods. The formation of intersected fracture channels is a necessary and sufficient condition for the occurrence and prediction of the water inrush disaster. Therefore, this paper focuses on studying a set of research methods for locating and understanding the mechanism of curtain water inrush channels. These methods encompass mining-induced fracture characterization, rock mass damage characterization, and water inrush channel identification based on moment tensor inversion (MTI). Finally, through a case study conducted at Zhangmatun Iron Mine, the proposed method successfully determines the location and formation mechanism of the curtain of the water inrush channel. This study presents a novel and feasible approach for analyzing curtain water inrush scenarios and provides a valuable reference for other mines facing the risk of grout curtain instability.