Magmatic fluids of Tatun volcanic group, Taiwan

Autor: Takeshi Ohba, Tsanyao Frank Yang, Noritoshi Morikawa, Hsiao Fen Lee, Kohei Kazahaya, Michiko Ohwada, Tefang Lan, Takeshi Sawa, Noriyasu Taira
Rok vydání: 2010
Předmět:
Zdroj: Applied Geochemistry. 25:513-523
ISSN: 0883-2927
DOI: 10.1016/j.apgeochem.2010.01.009
Popis: Two distinctive magmatic fluids were recognized in the Tatun volcanic group (TVG), Taiwan. One is a relatively reduced fluid represented by the fumarolic gases at Hsiao-you-ken (HYK) geothermal field. Another is an oxidized fluid containing high concentrations of HCl represented by the fumarolic gases at Da-you-ken (DYK). An intermediate gas was recognized at Gung-tze-ping (GTP) and She-hung-ping (SHP). The fumarolic gases at HYK and GTP possess the features of so-called primary steam generated on mixing of magmatic gas and meteoric groundwater. The fumarolic gases at DYK are a simple mixture between magmatic gas and water vapor of meteoric origin. The CO 2 /H 2 O molar ratio of the magmatic component in the fumarolic gases at DYK was estimated to be 0.018, meanwhile it was estimated to be 0.027 for the fumarolic gases at HYK and GTP, suggesting the magma beneath DYK is depleted in volatiles relative to the magma beneath HYK and GTP. The estimated CO 2 /H 2 O ratio for the magmatic component is comparable to that of some active volcanoes in Japan, suggesting the enrichment of volatiles in the magmas beneath TVG.
Databáze: OpenAIRE