Effects of an earthquake on the variations of hydrogeochemistry of groundwater - A review [Review - 지진에 의한 지하수의 수리지구화학적 변동에 대한 고찰]

Abstract

As a possible precursor of earthquakes, major ions, stable water isotopes and trace elements of groundwater and spring water have been monitored and analyzed for twenty years and mechanisms for the variations of hydrogeochemistry of groundwater have been suggested over the world. Although numerous physical variations associated with earthquakes are reported, the numbers of studies on hydrogeochemical variations of groundwater are not many, but continuously increasing. We will review the studies on responses of hydrogeochemistry of groundwater before and after earthquakes including major ions, stable water isotopes and trace elements and introduce mechanisms to explain the variations of hydrogeochemistry. Major ions, stable water isotopes and trace elements before and after earthquakes show some variabilities (increase or decrease), depending on the specific sites. Several mechanisms have been proposed to explain the variability and the mechanisms include co-seismic static stain inducing dilation and compaction; liquefication or consolidation of sediments; and permeability changed caused by shaking. However, it is required for comprehensive interpretation with long-term hydrogeochemical monitorings in the vicinity of areas related to seismic activities due to hydrogeological characteristics and the physical-chemical environment of groundwater covary for the specific sites. © 2020 The Geological Society of Korea. All rights reserved.