JpGU-AGU Joint Meeting 2017

Presentation information

[EJ] Oral

A (Atmospheric and Hydrospheric Sciences) » A-HW Hydrology & Water Environment

[A-HW35] [EJ] Isotope Hydrology 2017

Sat. May 20, 2017 10:45 AM - 12:15 PM 304 (International Conference Hall 3F)

convener:Masaya Yasuhara(Rissho Univ.), Kohei Kazahaya(Geological Survey of Japan, AIST), Kazuyoshi Asai(Geo Science Laboratory), Shinji Ohsawa(Institute for Geothermal Sciences, Graduate School of Science, Kyoto University), Chairperson:Hiroshi Takahashi(Geological Survey of Japan, National Institute of Advanced Industrial Science and Technology), Chairperson:Takashi Nakamura(Univ. Yamanashi), Chairperson:Kazuyoshi Asai(Geo-Science Laboratory), Chairperson:Masaya Yasuhara(Rissho Univ.)

11:05 AM - 11:25 AM

[AHW35-07] Isotope analysis of past drip water preserved as fluid-inclusions in stalagmites

★Invited papers

*Ryu Uemura1, Masashi Nakamoto1, Satoru Mishima1, Masakazu Gibo1, Ryuji Asami1, Chen Jin-Ping2, Chung-Che Wu2, Yu-Wei Chang2, Chuan-Chou Shen2 (1.University of the Ryukyus, 2.National Taiwan University)

Keywords:stable isotope, speleothem, fluid inclusioon

The oxygen isotope composition (δ18O) of speleothem is widely used as paleoclimate proxy. Interpretation of the δ18O value is not straightforward because it is controlled by two factors; δ18O of dripwater and temperature at calcite formation. The δ18O of speleothem fluid-inclusions, paleo-dripwaters in cave (i.e., paleo ground water), will provide an important constraint for the unknown quantity. Its paleoclimatic applications, however, have been hampered by technical difficulties for isotope measurements of fluid inclusions, recent developments of a new laser-based isotope ratio mass spectrometer have opened a new door of fluid inclusions analysis (e.g., Affolter et al., 2014; Arienzo et al., 2013). We also have developed a precise isotopic technique based on cavity ring-down spectroscopy with a low sample-amount requirement of 20-300 nL of inclusion water from stalagmites (Uemura et al., 2016). I will show detailed comparison with modern observation and recent results.