Abstract This paper deals mainly with acidic sulphate-chloride (ASC) waters that are discharged at volcanic edifices, generally, not associated with crater lakes. Geographically, the largest number of such manifestations were found on Japanese and Kuril Islands. These waters form by: (1) condensation of magmatic vapor under shallow conditions and/or (2) dissolution of magmatic gases in underground waters; (3) near-surface mixing of steam-heated sulphate waters with sodium-chloride waters of deeper formation; (4) interaction of sodium chloride waters with the rocks undergone by argillic and advanced-argillic alteration, including hydrolysis of elemental sulfur; (5) a combination of several of the listed processes. Criteria to assess the nature of such waters using their chemical and isotopic composition are based on the relative abundances of major species and trends in isotopic compositions generally controlling by mixing of magmatic-host rock-meteoric endmembers. An overview of available data on temporal chemical variations of such waters shows that usually volcanic activity is marked by an increase in the SO4/Cl ratio during or after the eruptive event. The response on the volcanic activity depends on hydrogeological conditions that control the appearance of the ASC springs.

中文翻译：

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酸性硫酸盐-氯化物火山水；火山活动监测的形成和潜力

摘要 本文主要讨论在火山建筑物排放的酸性硫酸盐-氯化物 (ASC) 水，通常与火山口湖无关。从地理上讲，在日本和千岛群岛发现了数量最多的此类表现形式。这些水是通过以下方式形成的：(1) 浅层条件下岩浆蒸气的凝结和/或 (2) 地下水中岩浆气体的溶解；(3) 蒸汽加热的硫酸盐水与较深地层的氯化钠水在近地表混合；(4) 氯化钠水与经过泥质和高级泥质蚀变的岩石的相互作用，包括元素硫的水解；(5) 列出的几个过程的组合。使用它们的化学和同位素组成来评估这些水的性质的标准是基于主要物种的相对丰度和同位素组成的趋势，通常由岩浆-宿主岩石-陨石端元的混合控制。对此类水域时间化学变化的现有数据的概述表明，火山活动通常以喷发事件期间或之后 SO4/Cl 比率增加为标志。对火山活动的响应取决于控制 ASC 泉水外观的水文地质条件。对此类水域时间化学变化的现有数据的概述表明，火山活动通常以喷发事件期间或之后 SO4/Cl 比率增加为标志。对火山活动的响应取决于控制 ASC 泉水外观的水文地质条件。对此类水域时间化学变化的现有数据的概述表明，火山活动通常以喷发事件期间或之后 SO4/Cl 比率增加为标志。对火山活动的响应取决于控制 ASC 泉水外观的水文地质条件。