Abstract

Oxygen and hydrogen isotopic compositions of stream water in the Han river basin are expressed by the equation of δD=6.6δ¹⁸O-7.4, which is not satisfy the meteoric water line (δD=8δ¹⁸O+10). It might be depended on the local climatic condition and the evaporation effect in the Han river basin. The δ18O and δD values of stream water in the Han river basin range from -8.2 to -10‰ (avg. -9.1‰) and -60 to -96‰ (avg. -69‰), respectively. The stream water from the South Han river (δ¹⁸O= -8.9~ -10‰, avg. -9.3‰ δD= -66~ -96‰, avg. -69‰) is slightly more depleted in ¹⁸O and D than those of North Han river (δ¹⁸O= -8.4~ -9.7‰, avg. -9.2‰, δD= -64~ -95‰, avg.-69‰). It reflects more altitude effect than the effect of latitude and inflow of the ¹⁸O enriched SO₄^2- and HCO₃^- from the carbonate rock and sulfide minerals in the Taebagsan and Hwanggangri mineralized zone. The Main stream water of the Han river having δD= -60~ -76‰ (avg. -68‰) and δ18O= -8.2~ -10‰ (avg. 9.0‰) is enriched in ¹⁸O compared to the South and North Han river waters, which is caused by the evaporation effect. Binary simple mixing ratio of the Main Han river water between South and North Han river waters was obtained to be 6 : 4 by the isotopic data, suggesting a strong influence of South Han river water to the Main Han river water.

Keywords oxygen and hydrogen isotopic compositions, stream water, Han river basin, altitude effect, evaporation effect.