岡山大学 地球科学研究報告
Published by Okayama University Earth Science Reports Editorial Committee

Hydrogen and oxygen isotope rations of thermal waters of Izu Peninsula, Shizuoka Prefecture, Japan

Kobyashi, Daiju
Yamamoto Masahiro
Abstract
Hydrogen and oxygen isotope ratios of thermal waters from 42 hot springs in Izu Peninsula, Shizuoka Prefecture, range from -51.7 to -24.7% in δD and from -7.9 to -4.1% in δ18O, respectively. The isotope ratios suggest that most of the thermal waters in Izu Peninsula are essentially meteoric in origin. Significantly deviated from the normal meteoric waters are thermal waters from Yumigahama, Kumomi, and Shimogamo hot springs which may be mixtures of seawater and local meteoric waters, and thermal waters from Izusan and Imaihama whose oxygen isotope ratios may have become heavier by water-rock interaction. 
Keywords
Hydrogen isotope ratio
Oxygen isotope ratio
Thermal water
Hot spring
Izu Peninsula
Shizuoka Prefecture
ISSN
1340-7414
NCID
AN10506284