Spatial distribution of δD-δ¹⁸O values of surface and shallow groundwaters from Japan, south Korea and east China

Abstract

Spatial distribution of δD and δ¹⁸O values of surface water and shallow groundwaters from Japan, south Korea and east China was mapped with contours of 10 and 1‰ intervals for δD and δ¹⁸O, respectively, on the basis of the data base including more than 600 analyses made in the present and previous studies. The δD and δ¹⁸O values generally decrease with increasing the latitude. There is a systematic decrease in δD and δ¹⁸O values with contours of close intervals from the coast toward inland of southwestern Japan along the stream of the Kuroshio, a warm current in the Pacific Ocean. The δD and δ¹⁸O lows are observed in mountainous inland of central and northern Japan and east China. The trends are comparable with those observed previously for the North American continent. The map will provide fundamental information for the studies of geochemical processes such as hydrology, water-rock interaction, and precipitation of authigenic minerals in which meteoric water is involved.