Abstract:
Seismic hydrogeology, as a cross-disciplinary field studying the interactions between seismic events and groundwater systems, aims to address the lack of systematic review and unclear definition of the scope and connotations within this field. This paper presents a comprehensive review of recent progress in seismic hydrogeology and outlines future research directions. By systematically consulting domestic and international literature on seismic hydrogeology and integrating the research progress of the team, this study explores the discipline's connotation, mechanisms of typical seismic hydrological phenomena, and future development directions. Results indicate that seismic hydrogeology mainly encompasses the impacts of earthquakes on groundwater systems, such as aquifer structure, hydraulic properties, groundwater levels, quantities, and chemistry, and the role of groundwater in earthquake preparation, triggering, and induced phenomena, involving the coupling of geophysical fields, deformation fields, and groundwater dynamics, chemical, and thermal fields. Earthquakes alter aquifer permeability, storage capacity, and cross-aquifer hydraulic connectivity via static strain and dynamic stress, forming mechanistic models such as particle mobilization, micro-fracture reconstruction, and breaching of confining layers. Groundwater level responses manifest as oscillations, step changes, and sustained changes, serving as precursors or co-seismic indicators of tectonic stress evolution. Changes in seismic-hydrogeochemical characteristics are controlled by fluid mixing, enhanced water-rock interactions, and deep-seated material upwelling, providing critical insights into fault activity. Pore pressure diffusion and poroelastic response are the dominant mechanisms for groundwater-induced or triggered earthquakes, driving instability of critical faults by altering effective normal stress. Seismic hydrogeology is evolving from qualitative descriptions toward quantitative mechanistic analyses. Future research should focus on the coupling mechanisms between earthquakes and groundwater systems, emphasizing multi-field coupling theories and deep processes. It should also strengthen the development of multi-field coupling models, experimental observations, multi-source data monitoring, and the integration of artificial intelligence technology. Advancing these research areas holds significant importance for understanding the coupling mechanisms of deep crustal dynamics and groundwater cycling between deep and shallow systems, as well as for mitigating earthquake-induced geological hazards and safeguarding national resources and environmental security.