Mechanism analysis of hazards caused by the interaction between groundwater and geo-environment

Groundwater is as an important geological agent. Moving groundwater may change the geological environment and cause geological hazards. Therefore, the interaction between groundwater and geo-environment has attracted increasing attention of hydrogeologists, geotechnical engineers and environmental geologists. In general, three main types of interaction between groundwater and the geological environment are identified in this paper, with several special processes for each one. These types include physical interaction, with processes of lubrication, softening or weakening and strengthening of bound water, chemical interaction with processes of ion exchange, dissolution, hydration, hydrolysis, corrosion and oxidation-reduction, and mechanical interaction with processes of hydrostatic pressure and hydrodynamic pressure. The interactions between groundwater and the geological environment can affect the deformability and strength of rock or soil masses. The geological process, engineering activity and heat can change the geo-stress field, recharge, throughflow and discharge conditions of groundwater. The consequence of interactions between groundwater flow and geo-stress changes the geological environment. Meanwhile, the interaction processes can induce geological hazards, such as reservoir-induced earthquakes, landslides, flooding of mines, ground engineering hazards, instability of dams, the collapse of cavities in carbonate and evaporate rocks, land subsidence and earthquakes.