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Volume 54 Supplement 3

Special Issue: Satsuma-Iwojima: Continuous degassing of a rhyolitic volcano

Soil gas emission of volcanic CO2 at Satsuma-Iwojima volcano, Japan


Soil gas surveys were carried out in November 1999 and October 2000 at Satsuma-Iwojma volcano, southwest Japan. The chemical composition of the soil gas was a mixture of CO2 and air components, with CO2 concentrations ranging from 0.03 to 59 vol%. The origin of the soil CO2 was evaluated on the basis of the variation of δ13CCO2 and CO2 concentration. Although most of the CO2 is of biogenic origin, large volcanic contributions of greater than 50% were found close to the caldera rim, where soil temperature anomalies were observed. Emission rate of volcanic CO2 was estimated by assuming simple mixing among volcanic, atmospheric, and biogenic CO2. High rates of diffuse emission of volcanic CO2 were also observed at the caldera rim and close to some hot springs, indicating that part of the volcanic-gas discharge ascends through fissures along the caldera rim. The flux of the volcanic CO2 through the soil is estimated to be 20 t day−1; this is 25% of the total CO2 flux through soil and 20% of the CO2 flux from volcanic fumaroles in the main crater of Iwodake.


  • Allard, P., J. Carbonelle, D. Dajlevic, J. LeBronce, P. Morel, M. C. Robe, J. M. Maurenads, R. Faivre-Pierret, D. Martin, J. C. Sabroux, and P. Zettwoog, Eruptive and diffuse emissions of CO2 from Mount Etna, Nature, 351, 387–391, 1991.

    Article  Google Scholar 

  • Baubron, J. C., P. Allard, and J. P. Toutain, Diffuse volcanic emissions of carbon dioxide from Vulcano Island, Italy, Nature, 344, 51–53, 1990.

    Article  Google Scholar 

  • Cerling, T. E., D. K. Solomon, J. Quade, and J. R. Bowman, On the isotopic composition of carbon in soil carbon dioxide, Geochim. Cosmochim. Acta, 55, 3403–3405, 1991.

    Article  Google Scholar 

  • Chiodini, G., F. Frondini, and B. Raco, Diffuse emission of CO2 from Fossa crater, Vulcano Island (Italy), Bull. Volcanol., 58, 41–50, 1996.

    Article  Google Scholar 

  • Chiodini, G., R. Cioni, M. Guidi, B. Raco, and L. Marini, Soil CO2 flux measurements in volcanic and geothermal areas, Appl. Geochem., 13, 543–552, 1998.

    Article  Google Scholar 

  • Gerlach, T., M. Doukas, K. McGee, and R. Kessler, Three-year decline of magamtic CO2 emission from soils of a Mammoth Mountain tree kill: Horseshoe Lake, CA, 1995–1997, Geophys. Res. Lett., 25, 1947–1950, 1998.

    Article  Google Scholar 

  • Gimmanco, S., S. Gurrieri, and M. Valenza, Soil CO2 degassing on Mount Etna (Sicily) during the period 1989–1993: discrimination between climatic and volcanic influences, Bull. Volcanol., 57, 52–60, 1995.

    Google Scholar 

  • Gimmanco, S., S. Gurrieri, and M. Valenza, Anomalous soil CO2 degassing in relation to faults and eruptive fissures on Mount Etna (Sicily, Italy), Bull. Volcanol., 60, 252–259, 1998.

    Article  Google Scholar 

  • Hernandez, P. A., N. M. Perez, J. M. Salazar, K. Notsu, and H. Wakita, Diffuse emission of carbon dioxide, methane, and helium-3 from Teide volcano, Tenerife, Canary Islands, Geophys. Res. Lett., 25, 3311–3314, 1998.

    Article  Google Scholar 

  • Hernandez, P. A., K. Notsu, J. M. Salazar, T. Mori, G. Natale, H. Okada, G. Virgili, Y. Shimoike, M. Sato, and N. M. Perez, Carbon dioxide degassing by advective flow from Usu volcano, Japan, Science, 292, 83–86, 2001a.

    Article  Google Scholar 

  • Hernandez, P. A., J. M. Salazar, Y. Shimoike, T. Mori, K. Notsu, and N. M. Perez, Diffuse emission of CO2 from Miyakejima volcano, Japan, Chem. Geol., 177, 175–185, 2001b.

    Article  Google Scholar 

  • Kamada, M., Volcanoes and geothermy of Satsuma-Iwojima, Kagoshima prefecture, Japan Geothermal Energy Association Journal, 3, 1–20, 1964.

    Google Scholar 

  • Kazahaya, K., H. Shinohara, and G. Saito, Degassing process of Satsuma-Iwojima volcano, Japan: Supply of volatile components from a deep magma chamber, Earth Planets Space, 54, this issue, 327–335, 2002.

    Article  Google Scholar 

  • Kita, I., S. Matsuo, and H. Wakita, H2 generation by reaction between H2O and crushed rock: An experiment study on H2 degassing from the active fault zone, J. Geophys. Res., 87, 10789–10795, 1982.

    Article  Google Scholar 

  • Nogami, K., M. Yoshida, and J. Ossaka, Chemical composition of discolored seawater around Satsuma-Iwojima, Kagoshima, Japan, Bull. Volcanol. Soc. Japan, 38, 71–77, 1993.

    Google Scholar 

  • Ono, K., T. Soya, and T. Hosono, Geology of Satsuma-Iojima district, Quadrangle series, scale 1:50,000, Tanegashima (16) No. 2, Geol. Surv. Japan, 1982 (in Japanese with English abstract).

  • Parkinson, K. J., An improved method for measuring soil respiration in the field, J. Appl. Ecol., 18, 221–228, 1981.

    Article  Google Scholar 

  • Shimoike, Y., Studies on the temporal variation of volcanic gas chemistry and on the diffuse degassing of volcanic gas, Dr. Thesis (Univ. Tokyo), pp. 104, 1999 (in Japanese).

  • Shinohara, H., W. F. Giggenbach, K. Kazahaya, and J. W. Hedenquist, Geochemistry of volcanic gases and hot springs of Satsuma-Iwojima, Japan: Following Matsuo, Geochem. J., 27, 271–285, 1993.

    Article  Google Scholar 

  • Shinohara, H., K. Kazahaya, G. Saito, N. Matsushima, and Y. Kawanabe, Degassing activity from Iwodake rhyolitic cone, Satsuma-Iwojma volcano, Japan: Formation of a new dagassing vent, 1990–1999, Earth Planets Space, 54, this issue, 175–185, 2002.

    Article  Google Scholar 

  • Sugisaki, R., M. Ido, H. Takeda, Y. Isobe, Y. Hayashi, N. Nakamura, H. Satake, and Y. Mizutani, Origin of hydrogen and carbon dioxide in fault gases and its relation to fault activity, J. Geol., 91(3), 239–258, 1983.

    Article  Google Scholar 

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Shimoike, Y., Kazahaya, K. & Shinohara, H. Soil gas emission of volcanic CO2 at Satsuma-Iwojima volcano, Japan. Earth Planet Sp 54, 239–247 (2002).

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  • Carbon Isotope Ratio
  • Summit Crater
  • Biogenic Origin
  • Diffuse Emission
  • Summit Area