Monitoring Changes in Seismic Velocity Related to Magmatism at Augustine and Veniaminof Volcanoes, Alaska

这项研究将集中于改善在阿拉斯加的奥古斯丁火山和威尼斯火山的活火山活动之前的前兆活动检测。研究人员将利用这些火山记录的环境噪声进行地震干涉测量，特别是2002年至2013年的Veniaminof火山爆发前后和2006年的Augustine火山爆发。这种方法能够解决台站对之间地震速度的微小时间变化，从而可以探测到火山随时间的细微变化。这项工作的自然延伸将包括奥古斯丁火山喷发前后地震速度时间变化的空间测绘。奥古斯丁地震速度变化的空间制图将有助于可视化火山喷发前后的结构变化。一些与奥古斯丁的岩浆储存和运输有关的重要问题将被研究，包括是否存在膨胀的浅层岩浆储层，以及浅层岩浆储层在喷发周期的哪一点膨胀。这项工作将寻找来自浅层岩浆储层的岩浆流体的迹象，以及作为喷发早期指标的上层地壳速度结构的扰动。在Veniaminof，他们将研究导致火山喷发的岩浆活动进程相关的问题，包括火山喷发前是否有岩浆储层膨胀的迹象，以及岩浆储层膨胀之后是否有岩浆流体向浅层迁移。奥古斯丁火山是库克湾最活跃的火山之一，而威尼斯火山是阿留申岛弧最活跃的火山之一。因此，两座火山对当地居民、空中交通、石油生产设施和航运活动都构成了重大威胁。这项研究将提高我们在奥古斯丁和威尼斯火山探测导致活火山活动的前兆活动的能力。这项拟议中的研究还将资助威斯康星大学麦迪逊分校（University of Wisconsin, Madison）的一位早期职业女性科学家尼法·本宁顿（Ninfa Bennington）博士。研究人员将创建一个在线网站，显示奥古斯丁火山和威尼斯火山地震速度的近乎实时变化。这个网站将提供给公众作为教育资源，同时也提供给AVO作为评估奥古斯丁和威尼斯火山活动的近实时监测工具。

This study will focus on improving the detection of precursory activity prior to active volcanism at both Augustine and Veniaminof volcanoes, Alaska. The researchers in the study will carry out seismic interferometry using ambient noise recorded at these volcanoes, specifically pre- through post-eruption for the 2002 through 2013 eruptions at Veniaminof and the 2006 Augustine eruption. This method is able to resolve small temporal changes in seismic velocity between station pairs, thus allowing the detection of subtle changes in the volcano over time. A natural extension of this work will include spatial mapping of these temporal changes in seismic velocity from pre- through post-eruption at Augustine volcano. Spatial mapping of these changes in seismic velocity at Augustine will help visualize pre- through post-eruptive structural changes at the volcano. Some important questions related to magma storage and transport at Augustine will be examined including if an inflating shallow magma reservoir exists, and at what point in the eruptive cycle does the shallow magma reservoir inflate. The work will look for indications of magmatic fluid from a shallow magma reservoir, and perturbations to the upper crustal velocity structure serving as an early indicator of eruption. At Veniaminof, they will examine questions related to the progression of magmatic activity leading to eruption, including if there are indications of an inflating magma reservoir prior to eruption, and if inflation of the magma reservoir is followed by the migration of magmatic fluids to shallow depths. Augustine volcano is one of the most active volcanoes in the Cook Inlet and Veniaminof volcano is one of the most active volcanoes in the Aleutian Arc. As such, both volcanoes pose major hazards to local people, air traffic, oil production facilities, and shipping activity. This study will improve our ability to detect precursory activity leading to active volcanism at both Augustine and Veniaminof volcanoes. The proposed study will also fund an early career female scientist, Dr. Ninfa Bennington, at the University of Wisconsin, Madison. The researchers will create an online website that displays near-real time changes in seismic velocity for both Augustine and Veniaminof volcanoes. This website will be available to both to the general public as an educational resource and to the AVO as a near-real time monitoring tool to assess volcanic activity at Augustine and Veniaminof volcanoes.