Fluxes of deep CO₂ in the volcanic areas of central-southern Italy

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• 作者：Barbara Gambardella ; Carlo Cardellini ; Giovanni Chiodini ; Francesco Frondini ; Luigi Marini ; Giulio Ottonello ; Marino Vetuschi Zuccolini
• 关键词：earth degassing ; carbon dioxide ; CO₂ ; central-southern Italy ; volcanic groundwater
• 刊名：Journal of Volcanology and Geothermal Research
• 出版年：2004
• 出版时间：30 August 2004
• 年：2004
• 卷：136
• 期：1-2
• 页码：31-52
• 全文大小：1064 K

文摘

Both the shallow (organic-derived) and deep (mantellic–magmatic–metamorphic) fluxes of CO₂ [Φ_CO2, mass time⁻¹] and specific fluxes of CO₂ [_CO2 mass time⁻¹ surface⁻¹] dissolving in the shallow groundwaters of the volcanic areas of Amiata, Vulsini-Vico-Sabatini, Albani, Roccamonfina, Vesuvio, Vulture, and Etna were evaluated by partitioning the composed population of total dissolved inorganic carbon in two individual populations and subsequent subtraction of local background population.

The flux of deep CO₂ released from the geothermal fields of Piancastagnaio (Amiata), Torre Alfina, Latera, Marta, Bracciano south, Cesano, and Mofete and from the Overall Northern Latium Hydrothermal Reservoir were also evaluated by means of the total surface heat flux and the enthalpy and CO₂ molality of the single liquid phase circulating in each geothermal reservoir.

These data suggest that the _CO2 released to the atmosphere varies from 9.5×10⁶ to 3.0×10⁶ mol year⁻¹ km⁻², over the geothermal fields of Bracciano south and Cesano, respectively, and that a total Φ_CO2 of 3.8×10⁸ mol year⁻¹ is cumulatively released from the geothermal fields of Torre Alfina, Latera and Cesano extending over an area of only 66 km².

In addition, a flux of 2.2×10¹¹ to 3.8×10¹¹ mol year⁻¹ of gaseous CO₂ entering the atmosphere is obtained for the entire anomalous area of central Italy, extending from the Tyrrhenian coastline to the Apennine chain (45,000 km²). Thus terrestrial CO₂ emission in central-southern Italy appears to be a significant carbon source.