Progress and challenges in studies of earthquake rupture initiation and arrest

Research on the initiation, evolution, and arrest of earthquake ruptures represents a central frontier in global seismology and provides a critical scientific foundation for national needs such as earthquake early warning, short-term prediction, and disaster mitigation. With rapid advances in fundamental Earth science theory, observational technologies, and artificial intelligence methods, as well as the deepening integration of multiple disciplines, research on the physical mechanisms governing earthquake initiation, dynamic rupture acceleration, and eventual arrest urgently needs to shift toward a comprehensive paradigm characterized by quantitative constraints, empirical verification, and multi-scale coupling. This paper provides a systematic review of major scientific progress in this field, focusing on eight key aspects: earthquake nucleation and rupture processes, high-resolution three-dimensional source-zone structure and its temporal variations, long-term fault-zone evolution and kinematics, rock-physics experiments and numerical modeling, rupture mechanisms across nano-micro-mesoscale heterogeneous media, in-situ seismic observation and advanced analysis techniques, physical mechanisms of earthquake nucleation, and intelligent interpretation of complex seismic processes. We summarize the overarching scientific objectives of studying earthquake initiation and termination, distill the critical scientific and technical challenges that demand urgent attention, and offer recommendations for strengthening empirical constraints on source processes. Finally, we propose priority research directions and strategic development pathways for the next 5–10 years in the fundamental study of earthquake initiation and arrest mechanisms.