SPATIAL-DISTRIBUTION OF DELTA-D-DELTA-O-18 VALUES OF SURFACE AND SHALLOW GROUNDWATERS FROM JAPAN, SOUTH-KOREA AND EAST CHINA

Spatial distribution of delta D and delta(18)O values of surface water and shallow groundwaters from Japan, south Korea and east China was m apped with contours of 10 and 1 parts per thousand intervals for delta D and parts per thousand(18)O, respectively, on the basis of the data base including more than 600 analyses made in the present and previou s studies. The delta D and delta(18)O values generally decrease with i ncreasing the latitude. There is a systematic decrease in delta D and delta(18)O values with contours of close intervals from the coast towa rd inland of southwestern Japan along the stream of the Kuroshio, a wa rm current in the Pacific Ocean. The delta D and delta(18)O lows are o bserved in mountainous inland of central and northern Japan and east C hina. The trends are comparable with those observed previously for the North American continent. The map will provide fundamental informatio n for the studies of geochemical processes such as hydrology, water-ro ck interaction, and precipitation of authigenic minerals in which mete oric water is involved.