A STUDY ON HYDRO-CHEMICAL PROCESSES OF GROUNDWATER OUTFLOW FROM DEEP-SEATED LANDSLIDES CAUSED BY TYPHOON TALAS IN 2011

Abstract

Hydro-chemical processes of groundwater outflow from deep-seated landslides are still incompletely understood. Groundwater outflow from deep-seated landslides show high electric conductivity. Since electric conductivity estimates the total amount of dissolved ions in the water, we focused on ions in the groundwater eluted from bedrocks. This study revealed conditions of increasing electric conductivity of groundwater and the ions effect on variation of electric conductivity. We grasped elution characteristics of bedrocks by conducting elution test of boring cores from deep-seated landslides. In conclusion, conditions of increasing electric conductivity of groundwater are (1) long-term groundwater flow, (2) groundwater flow in collapsed bedrocks, and (3) bedrocks exist in groundwater level. And the effective ions are hydrogen carbonate and calcium ion.