Collaborative Research: Investigating the Relationship Between Pluton Growth and Volcanism at Two Active Intrusions in the Central Andes

该奖项是根据2009年《美国复苏和再投资法案》(公法111-5)提供资金的。我们对地壳岩浆室如何演化以及这些岩浆室与深成岩和喷发的关系的了解还不充分，这主要是因为还没有人对活跃的地壳岩浆室进行全面的研究。该项目提供了这样做的独特机会，并将从根本上对地壳深部岩浆的生成、储存和分异提供新的见解。PI们设计了这个项目，利用了可能导致褐沸石喷发的早期阶段。考虑到从未观察到一次大规模的褐煤喷发，更不用说积累一次了，这可能是千载难逢的机会。该项目建立在最近的干涉合成孔径雷达结果的基础上，这些结果显示，位于安第斯山脉中部的几座火山上方有大规模的快速隆起。这项研究的重点是解决岩浆室的位置、大小和形状，以及它们填充的速度。InSAR、GPS大地测量和微重力测量的结合将为目前岩浆流动提供必要的数据。河流地貌将被用来估计较长时间内的隆升速率。地震和大地电磁研究将提供有关任何岩浆室的位置和大小的独立信息。从通过岩浆形成地壳的方式到火山喷发的基本危险预测，岩浆在地壳中的运移机制对许多问题都非常重要。在建造中的大型中地壳岩浆室期间调查它的发展是促进我们对这一问题的理解的最好方式，而这一建议中的跨学科方法是关键。该项目包括与英国布里斯托尔大学的科学家密切合作，后者由NERC资助，并与智利、阿根廷和玻利维亚的研究小组密切合作。

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). Our knowledge of how crustal magma chambers evolve and how these magma chambers relate to plutons and eruptions is inadequate, largely because nobody has yet conducted a comprehensive study of an active crustal magma chamber. This project provides a unique opportunity to do so and will provide fundamentally new insights into deep crustal magma generation, storage, and differentiation. The PIs have designed the project taking advantage of what may be the early stages leading up to an ignimbrite eruption. Given that a large ignimbrite eruption has never been observed, let alone the build-up to one, this might be a once in a many-generation opportunity. The project builds on recent InSAR results that show large-scale rapid uplift situated over several volcanoes in the Central Andes. The research is focused on resolving the location, size, and shape of the magma chambers, and the rates at which they are filling. The combination of InSAR, GPS geodesy, and microgravity measurements will provide the essential data for magma fluxes at present. Fluvial geomorphology will be used to estimate uplift rates over a longer time. Seismic and magnetotelluric studies will provide independent information about the location and size of any magma chamber. The mechanism of magma transport through the crust is very important for a number of issues ranging from the manner of crust formation via magma addition to basic hazard predictions for volcanic eruptions. Investigating the development of a large mid-crustal magma chamber while it is being built is the best way to advance our understanding of this issue and the interdisciplinary approach in this proposal is key. The project includes close collaboration with scientists from the University of Bristol (UK) who are funded by NERC and with research groups in Chile, Argentina and Bolivia.