Collaborative Research: The Magmatic and Eruptive System of Mount Erebus Volcano, Antarctica

合作研究：南极洲埃里伯斯火山的岩浆和喷发系统

• 批准号: 1917149
• 负责人: Ronni Grapenthin
• 金额: $ 16.2万
• 依托单位: New Mexico Institute of Mining and Technology
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-01 至 2020-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1917149&HistoricalAwards=false
• 关键词: Collaborative; Research; Magmatic; Eruptive; System

Mount Erebus, a volcano on Ross Island, Antarctica has been in a continuous state of open-vent activity for at least 45 years while hosting a long-lived lava lake at its summit. The volcano's proximity to the United States Antarctic Program McMurdo Station, its longstanding experimental infrastructure, and prior studies present opportunities to develop and apply cutting edge imaging methods to understand a persistently active volcanic system. This project will utilize data from a renovated five-station near-summit seismic network of Mt. Erebus plus three additional stations sited on the flanks of the volcano. This wide aperture network, paired with modern instrumentation and techniques to enhance seismic signal, will provide unprecedented imaging into the deep volcanic plumbing system at crustal scale, which will help researchers understand the volcano's complex structure and processes. Additionally, the network provides year-round seismic data to be used in temporal monitoring efforts for eruptive and other activity. All data from this network will be openly available in near real-time. The real-time data along with an existing catalog of archived data will be analyzed using recently developed methods to generalize, recognize, quantify, and catalog eruptive events. The project objectives are to study the response of the magmatic system to such events and use continuously recorded background noise and eruption signals to infer concurrent structural changes. These seismic investigations into the long-term changes of the volcano, tracking broad phenomena such as the subsidence of Ross Island, will also be complemented by GPS recordings of deformation. These activities will help test hypotheses related to the structure of the deeper magmatic system of Erebus and the properties of the material surrounding this system. The project funds two early-career scientists and three graduate students, contributing to the development of the next generation of volcanologists and seismologists.This award results in the establishment of a first-tier monitoring system and catalogues eruptive events using real-time seismic and infrasound data. Synoptic analysis of broadband signals recorded by the updated seismic network will allow monitoring and interpretation of pre and post eruptive response and conduit evolution via measurements of systematic timing changes of short-period (explosion) versus very long-period (conduit) seismogram signatures. These observations will be supplemented by the interpretation of broadband seismic tilt in association with existing UNAVCO-supported GPS data over time scales from hours to years. Longer-period coda correlation back projection will be used to refine upper edifice structural information and teleseismic signals will be analyzed to examine the bulk and discontinuity structure of the underlying crust. The work includes a reanalysis of archived TOMO Erebus broadband, as well as extensive short-period data collected in 2007-2008. This effort will allow new imaging and interpretation of deeper (e.g., crustal to Moho-or-deeper scale) structure than has been previously imaged at Erebus in consort with other constraints, such as emerging magnetotelluric imaging results for Erebus and Ross Island. The researchers will use the year-round continuous stations to time-lapse interrogate prominent and repeatable structural/internal scattering features revealed by both ambient noise and eruption or other signal coda correlations. Joint inversions of H/V ratios for both coda and ambient noise coupled with dispersion curves assembled from the fusion of ambient noise (low frequency) and coda (high frequency) will complement direct imaging of strong near-surface scatterers and will be applied to archived ETB/ETS data sets. Cutting edge reflection matrix techniques will continue to be developed in collaboration with independently funded groups in France to further isolate and define high scattering bodies within the top 10 kilometers of the crust and edifice. This award is cofunded by the Prediction of and Resilience against Extreme Events (PREEVENTS) program.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

南极洲罗斯岛上的埃里巴斯火山至少45年来一直处于持续的喷口活动状态，同时在其顶端拥有一个长寿的熔岩湖。这座火山靠近美国南极计划麦克默多站、其长期的实验基础设施，以及之前的研究，为开发和应用尖端成像方法了解持续活跃的火山系统提供了机会。该项目将利用翻新的山顶附近的五个台站地震台网的数据。埃里巴斯和另外三个空间站位于火山的侧翼。这个大口径网络，再加上增强地震信号的现代仪器和技术，将提供前所未有的地壳级别的深层火山管道系统的成像，这将有助于研究人员了解火山的复杂结构和过程。此外，该网络还提供全年地震数据，用于对火山喷发和其他活动进行时间监测。来自该网络的所有数据将以接近实时的方式公开可用。实时数据以及现有的存档数据目录将使用最近开发的方法进行分析，以概括、识别、量化和编目喷发事件。该项目的目标是研究岩浆系统对这类事件的反应，并利用连续记录的背景噪音和喷发信号来推断同时发生的构造变化。这些对火山长期变化的地震调查，追踪罗斯岛下沉等广泛现象，也将得到GPS变形记录的补充。这些活动将有助于检验与埃里巴斯更深的岩浆系统的结构和该系统周围物质的性质有关的假设。该项目资助了两名职业生涯初期的科学家和三名研究生，为培养下一代火山学家和地震学家做出了贡献。这项奖励的结果是建立了一级监测系统，并使用实时地震和次声数据对喷发事件进行了分类。对更新后的地震台网记录的宽带信号进行天气分析，将通过测量短周期(爆炸)和甚长周期(管道)地震记录特征的系统时间变化，监测和解释喷发前和喷发后的反应和管道演变。对这些观测结果的补充将是对宽带地震倾斜度的解释，并结合联阿援助团支持的现有全球定位系统数据，从数小时到数年不等。将使用较长周期的尾波相关反投影来提炼上部建筑物的结构信息，并将分析远震信号以检查下部地壳的块体和不连续结构。这项工作包括对已存档的Tomo Erebus宽带的重新分析，以及在2007-2008年收集的大量短期数据。这项工作将允许对埃里巴斯以前成像的更深(例如，地壳到莫霍面或更深的尺度)结构进行新的成像和解释，并结合其他限制因素，例如埃里巴斯和罗斯岛新出现的大地电磁成像结果。研究人员将使用全年连续的观测站对环境噪声和喷发或其他信号尾波相关性揭示的显著和可重复的结构/内部散射特征进行时间推移审问。尾波和环境噪声的H/V比的联合反演以及由环境噪声(低频)和尾波(高频)融合而成的色散曲线将补充强近地表散射体的直接成像，并将应用于存档的ETB/ETS数据集。尖端反射矩阵技术将继续与法国独立资助的团体合作开发，以进一步隔离和定义地壳和建筑物顶部10公里内的高散射体。该奖项由极端事件预测和抵御极端事件(PREEVENTS)计划共同资助。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。