Beppu hot springs

The Beppu hot springs are located at the eastern end of the Beppu-Shimabara Graben, Kyushu. The basement rocks are composed of Paleozoic crystalline schists and Cretaceous granitic rocks. Miocene to early Pleistocene andesitic rocks occur mainly in the southern part of the area, while lava domes of hornblende andesite which are younger than 100,000 years occur in the western part. 

The total amount of discharged hot spring water is 50,000 ton/day, indicating a huge geothermal system (Taguchi et al., 1988). 

The hot spring waters are divided into sulfate-rich steam heated water, chloride-rich deep-water, bicarbonate-dominated water and their intermediate types. 

The red precipitates in the Chino-ike Jigoku contain high concentration of base and precious metals (Au, 23 Ag, 383 As, 4440 Sb, 180 Pb, 14442 Zn, 104 Cu, 57 ppm, respectively) and consist of low cristobalite, tridymite, kaolinite, hematite and montmorillonite (Koga, 1961, 1972 Yamashita, 1977 Yoshida et al., 1978). 

The hot water of Jigoku is a mixture of sulfate-rich water and deep chloride-rich 

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In contrast to the estimation of total dissolved sulfur concentration (ES), the total dissolved selenium concentration (ESe) has not yet been estimated. The Beppu hot springs which are accompanied by Au-Ag siliceous sinter, contain about 10 moI/1 Se (Uzumasa, 1965). For the construction of Figs. 1.93 and 1.94, the Se/S ratio of the ore fluids is assumed to be 10 . ... 

Taguchi, S., Itoi, R. and Yusa, Y. (1988) Beppu hot springs. In Geothermal fields and geothermal power plants in Japan. Int. Symp. Geothermal Energy, Kumamoto and Beppu, Japan, November 10-14 pp. 119-124. 

Organism and Cell Culture. Sulfolobus sp. strain 7 (originally named S. acido-caldarius strain 7 isolated from Beppu hot springs, Kyushu, Japan ) is a strictly aerobic and thermoacidophilic crenarchaeote that grows optimally at 75-80° and at pH 2.5-3.0. The 16S rRNA sequence and biochemical analysis of the isolate suggested that it is a novel crenarchaeote, belonging to the genus Sulfolobus. ... 

Base-metal (Pb, Zn, Cu) mineralizations were reported from Okuaizu, Nigorikawa, Arima and Ibusuki geothermal areas as scale products and precipitates from hot springs. Gold precipitations from hot springs are known from the Osorezan volcano and Beppu. 

Koga, A. (1961) Gold distribution in the hot springs water in Beppu. J. Chem. Soc. Japan, 82, 1476-1478 (in Japanese). 

Koga, A. (1972) Chino-ike Jigoku, Beppu. Oita Prefecture Hot Spring Investigation Report, No. 23, 12—lA (in Japanese). 

Koga, A., 1961, Distribution of gold in hot springs at Beppu (in Japanese) Journal ofthe Chemical Society of Japan, v. 82, p. 1476-1478. 

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