Abstract In the Amiata volcanic–geothermal area, natural soil degassing of CO2 is particularly intense and observed over a wide area, including the volcano complex and its surroundings. A survey systematically and directly measured the natural total soil CO2 flux over the whole area, comprising 2482 measurements over an area approximately 225 km2. Sequential Gaussian simulations generated CO2 flux maps for the entire survey area. These data, when combined with evidence from concentrated degassing emissions, provided an estimate of the area's total CO2 flux (biogenic plus deep CO2) as 13,350 t/d. This mapping and estimation greatly improve the knowledge and understanding of natural CO2 degassing to the atmosphere from this well-known volcanic geothermal area. High values of diffuse CO2 soil flux correspond to both high- and low-enthalpy geothermal areas, confirming the value of the CO2 flux survey methodology to individualize and delimitate geothermal fields and geothermal resources.

中文翻译：

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阿米亚塔山火山-地热区自然二氧化碳脱气

摘要 在 Amiata 火山-地热区，CO2 的自然土壤脱气作用特别强烈，并且在包括火山复合体及其周边地区在内的广阔区域内都能观察到。一项调查系统地直接测量了整个地区的自然土壤 CO2 总通量，包括大约 225 平方公里区域内的 2482 次测量。连续高斯模拟生成了整个调查区域的 CO2 通量图。这些数据与集中脱气排放的证据相结合，估计该地区的总二氧化碳通量（生物源二氧化碳和深层二氧化碳）为 13,350 吨/天。这种绘图和估算极大地提高了对从这个著名的火山地热区向大气中自然脱气的 CO2 的认识和理解。