Carbogaseous spring waters, coldwater geysers and dry CO2 exhalations in the tectonic window of the Lower Engadine Valley, Switzerland
Carbogaseous spring waters, coldwater geysers and dry CO2 exhalations in the tectonic window of the Lower Engadine Valley, Switzerland
复制标题
瑞士下恩嘎丁山谷构造窗内的含碳泉水、冷水间歇泉和干二氧化碳呼出
DOI：
--
复制
发表时间：
2006
期刊：
影响因子：
--
通讯作者：
F. Vuataz
中科院分区：
文献类型：
--
作者：
Pius Bissig;N. Goldscheider;Joëlle Mayoraz;H. Surbeck;F. Vuataz
Abstract.In the region of Scuol-Tarasp in the Lower Engadine Valley in the Eastern Swiss Alps, there are a variety of phenomena related to a geogenetic CO2 production, including carbogaseous mineral springs, previously active coldwater geysers and dry gas exhalations from the ground via mofettes. Previous isotopic studies revealed that the CO2 originates from the metamorphic decomposition of carbonate rocks in the crust. This paper presents an inventory of the springs, geysers and mofettes, and proposes a conceptual model on the regional gas and water circulation. Based on hydrochemical criteria, it was possible to identify six main groups of spring waters, three of which are carbogaseous mineral springs. Most of the carbogaseous springs and gas exhalations are bound to the Bündnerschiefer fractured aquifer. The different water types originate from mixing of groundwater and highly mineralised carbogaseous fluids from depth. Near-surface degassing of CO2 from the fluid phase creates the dry gas exhalations. CO2 and radon measurements in 178 soil boreholes suggest that the gas exhalations occur at a limited number of point-like anomalies, and there is no evidence for regionally important diffuse CO2 discharges from the ground.Resumaziun.En la regiun da Scuol-Tarasp en l’Engiadina bassa, en l’orientala part dallas alps svizras cumparan antgins fenomens, che coreleschan cun la producziun da CO2 en la profunditad. Ei dat fontaunas mineralas carbonicas, antruras geisirs activs d’aua freida e sortidas da gas schetg da mofettas. Anteriuras retschercas d’isotops han mussau, ch’il CO2 deriva dalla decumposiziun metamorfosa da caltschina en la crusta dalla tiara. Questa lavur presenta in inventari da fontaunas, geisirs e moffettas e fa ina proposta per in model concepziunal per la circulaziun regiunala da gas ed aua. Sin fundament da criteris hidrochemics han sis gruppas da fontaunas saviu vegni identificadas, dallas qualas treis gruppas cumprendan fontaunas mineralas carbonicas. Las pliras fontaunas carbonicas neschan egl aquifer dil sfendaglius platter Grischun. Ils differents tips d’aua da fontauna resultan entras la mischeida da liquidas profundas carbonicas fetg mineralisadas cun auas sutterranas giuvnas. Degasaziun dil CO2 ord la fasa d’aua damaneivel da la surfatscha meina tier l’exhalaziun da gas. Mesiraziuns da CO2 e radon en 178 ruosnas indicheschan, che l’exhalaziun da gas serestrenscha sin paucas anomalias punctualas. Ei dat negins indezis per ina impurtonta sortida regiunala da CO2.
