SREL Reprint #2993




Geochemistry and Microbiology of Hot Springs in Kamchatka, Russia

Weidong Zhao1,2, Christopher S. Romanek2,4, Gary Mills2,4, Juergen Wiegel3, and Chanlun Zhang1,2

1Department of Marine Sciences, University of Georgia, Athens, Georgia 30602, USA
2Savannah River Ecology Laboratory, University of Georgia, Aiken, South Carolina 29802, USA
3Department of Microbiology, University of Georgia, Athens, Georgia 30602, USA
4Department of Geology, University of Georgia, Athens, Georgia 30605, USA

Abstract: Kamchatka is one of the most active regions of volcanism in the world because it is located in the transitional zone where the Eurasian plate, North American plate and Pacific plates meet. As a result, Kamchatka has numerous hydrothermal systems, which constantly release geothermal gases and fluids out to the earth surface. Geothermal gases such as N2 and CO2 may prevail in the outflows but H2, CH4 and H2S occur frequently. Hot spring waters in Kamchatka may have multiple origins including meteoric and magmatic water. The temperature of these hot springs ranges from ~20oC to greater than 90oC. Water chemistry also varies dramatically with pH ranging from 3.1 to 9.8. Hydrothermal fluids are sodium chloride water dominant and may contain various dissolved constituents including K+, H3BO3, H4SiO4, Ca2+, and SO42-. Volcanic ore-formation prevails in the high thermal activity regions in Kamchatka and precipitates may be dominated by silica crusts, sulfur and Hg-Sb-As-FeS deposits. Oils are also generated in the region and dominated by n-alkanes.

More than 24 novel thermophilic microorganisms have been isolated from hot springs in Kamchatka. Most of these isolates are heterotrophs; however, autotrophs may be equally abundant depending on the spring conditions. Collectively, these organisms may play important roles in biogeochemical cycling of carbon, sulfur, and iron in the hydrothermal system. Culture-independent approaches and quantitative methods are now employed to enhance our understanding of the ecology and biogeochemical functions of microorganisms in Kamchatka hot springs.

Key-words: Hot springs; geochemistry; microbiology; Kamchatka

SREL Reprint #2993

Zhao, W., C. S. Romanek, G. Mills, J. Wiegel, and C. L. Zhang. 2005. Geochemistry and Microbiology of Hot Springs in Kamchatka, Russia. Geological Journal of China Universities 11(2):217-223.

To request a reprint