Structure of Active Fumarole Fields: An Integrated Geophysical and Geochemical Approach

活跃喷气孔场的结构：综合地球物理和地球化学方法

• 批准号: 9206048
• 负责人: Charles Connor
• 金额: --
• 依托单位: Florida International University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-07-01 至 1995-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9206048&HistoricalAwards=false
• 关键词: Structure; Active; Fumarole; Fields; Integrated

Physical models of flow in medium- and high-temperature fumarole fields suggest that mass flow will exert a strong control on fumarole temperature in most circumstances. The PIs plan to monitor temperature and mass flow continuously to test this relationship in three active fields. These fields are on Volcano Colima, Mexico, Poas, Costa Rica, and Galeras, Colombia, and encompass a range of hydrothermal regimes. At Galeras, young fumaroles are likely a manifestation of forced convection of magmatic and deeply circulating meteoritic fluids. At Poas, shallow free convection likely dominates flow. Colima represents a flow regime intermediate between the other two. The time scales and interdependence of temperature, mass flow, and geochemistry will vary between these systems. Geochemical data, particularly stable and cosmogenic isotopes, will help distinguish more clearly between shallow free convection and fumaroles fed by forced convection from relatively deep or magmatic sources. Differentiation of these transport mechanisms is important to the understanding and interpretation of observed changes in fumarole activity at active volcanoes.

中高温喷气孔场中流动的物理模型表明，在大多数情况下，质量流将对喷气孔温度产生强有力的控制。 PI 计划持续监测温度和质量流量，以测试三个活跃领域的这种关系。这些油田位于墨西哥科利马火山、哥斯达黎加波阿斯和哥伦比亚加莱拉斯，涵盖一系列热液区域。在加勒拉斯，年轻的喷气孔很可能是岩浆和深层循环陨石液体强制对流的表现。在波阿斯，浅层自由对流可能占主导地位。科利马代表介于其他两者之间的流态。这些系统之间的时间尺度和温度、质量流量和地球化学的相互依赖性会有所不同。地球化学数据，特别是稳定和宇宙成因同位素，将有助于更清楚地区分浅层自由对流和来自相对较深或岩浆来源的强制对流的喷气孔。这些传输机制的区分对于理解和解释观察到的活火山喷气孔活动的变化非常重要。