Time Dependent Deformation of Galapagos Sheild Volcanoes Observed with Radar Interferometry

用雷达干涉测量法观测加拉帕戈斯盾火山的随时间变形

• 批准号: 0343030
• 负责人: Falk Amelung
• 金额: $ 7.55万
• 依托单位: University of Miami
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-05-01 至 2005-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0343030&HistoricalAwards=false
• 关键词: Time; Dependent; Deformation; Galapagos; Sheild

Amelung EAR-0003542 The Galapagos shield volcanoes on the islands of Fernandina and Isabela are among the most active volcanoes on Earth with an average of 2-3 eruptions every 10 years. The investigator's previous radar interferometric study demonstrated how actively the Galapagos volcanoes deform, and how well this can be measured with radar interferometry. All but one of the 7 volcanoes show evidence for magma intrusion resulting in uplift of the volcanic edifice at rates between a few mm/yr to 0.9 m/yr (Amelung et al., 2000). In this project the investigators will obtain a dense time series of interferograms to map, document and interpret the deformation of Galapagos volcanoes with high temporal resolution (~35-70 days). A dense time series of interferograms will address the following issues: Do subsurface magmatic intrusions occur in pulses or are they continuous in time? If in pulses, how long do they last? Does the intrusion rate increase prior to an eruption? Is the center of magmatic inflation stationary or does it migrate vertically or horizontally prior to an eruption? Do intrusions at different volcanoes occur simultaneously or are they separated in time? Are the volcanoes fed by a common or by different deep magma sources? These questions should be addressed by the dense spatial and time coverage the proposed InSAR observations.

位于费尔南迪纳岛和伊萨贝拉岛上的加拉帕戈斯盾状火山是地球上最活跃的火山之一，平均每10年喷发2-3次。研究人员先前的雷达干涉研究证明了加拉帕戈斯火山变形的活跃程度，以及雷达干涉测量法的测量效果。7座火山中除一座外，所有火山都显示出岩浆侵入的证据，导致火山建筑物以几毫米/年至0.9米/年的速度抬升（Amelung等人，2000年）。在该项目中，调查人员将获得密集的干涉图时间序列，以高时间分辨率（约35-70天）绘制、记录和解释加拉帕戈斯火山的变形。一个密集的时间序列的干涉图将解决以下问题：地下岩浆侵入发生在脉冲或连续的时间？如果是脉冲式的，它们会持续多久？火山爆发前侵入率增加了吗？岩浆膨胀的中心是静止的，还是在喷发前垂直或水平移动？不同火山的侵入是同时发生的，还是在时间上分开的？这些火山是由共同的还是不同的深层岩浆源供给的？这些问题应该通过拟议的干涉合成孔径雷达观测的密集空间和时间覆盖来解决。