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¡ ¢ ­ ®+A Brief Review of Earth Scientiﬁc Studiesof the Beppu Hydrothermal Field,
Kyushu Island, Japan
Yuki YUSA+

Abstract
An outline of earth scientiﬁc studies carried out in the Beppu hydrothermal ﬁeld,
which is one of the largest hydrothermal ﬁelds in Japan, during +3,*’s through the ﬁrst
half of ,***’s. Studies are hydraulics of groundwater, evaluation of outputs of water, heatand chloride ion, and modeling of hydrothermal processes including estimation of temperature and chloride ion content of parent thermal water. It is required to clarify physical and chemical properties of supercritical water ascending from deep layer.
Key words : Beppu hydrothermal ﬁeld, History, Earth sciences, Episodes, Beppu Geothermal
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Allis, R.G. and Yusa, Y. (+323) : Fluid ﬂow processes in the Beppu geothermal system, Japan.
Geothermics, +2, 1.-῍1/3.

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Kitaoka, K. (+33*) : Water circulation rates in a geothermal ﬁeld. A study of tritium in the
Beppu hydrothermal system, Japan. Geothermics, +3, /+/ῌ/-3.

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Ohsawa, S., Kawamura, T., Takamatsu, N. and Yusa, Y. (,***) : Rayleigh scattering by aqueous colloidal silica as a cause for the blue color of hydrothermal water. J. Volcanol.
Geotherm. Res., ++-, .3ῌ0*.
Ponting, H.G. (+3++) : In Lotus-Land Japan, Macmillan Co. Ltd, London.

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Yusa, Y. and Ohsawa, S. (,***) : Age of the Beppu hydrothermal system, Japan. Proc. World
Geothermal Congress ,***, -**/ῌ-**2.

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