Estimation of Amounts of Weathered Products through Chemical Composition of Waters in the Kamenose Landslide Area

Abstract

136 water samples have been collected from the Kamenose landslide area, Osaka Prefecture, to estimate the amounts of weathered products through the chemical composition of the waters. We have examined the relationships among the chemical species contents of the waters and the interaction of silicate minerals with the waters, and the following have been obtained : The amounts of montmorillonite and kaolinite produced by CO_2-bearing waters reacting with parent rocks are estimated as 49 tons/year (60 g/m^2/year) and 40 tons/year (50 g/m^2/year), respectively ; the total amount of weathering rocks is estimated as 150 tons/year (190 g/m^2/year) ; the waters are in equilibrium with kaolinite and montmorillonite ; coexistence of both kaolinite and montmorillonite is maintained only under the condition of bicarbonate content over about 60 mg/l.