Collaborative Research: The dynamics of Mauna Loa's and Kilauea's magmatic systems from physics-based modeling

合作研究：基于物理建模的莫纳罗亚火山和基拉韦厄火山岩浆系统的动力学

• 批准号: 1331125
• 负责人: James Foster
• 金额: $ 8.63万
• 依托单位: University of Hawaii
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-08-01 至 2016-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1331125&HistoricalAwards=false
• 关键词: Collaborative; Research; dynamics; Mauna; Loa

Dynamic linkage between volcanoes has implications for long- and short-term eruption forecasting. Although such linkage has been suggested to exist for some volcanic systems it remains controversial, as does the underlying mechanism. Recently, the possibility of dynamical coupling of Kilauea and Mauna Loa has been proposed as a consequence of pressure diffusion within an asthenospheric melt zone that underlies both volcanoes, and from which each volcano is supplied with melt, albeit from different parts of it. To test this hypothesis, we propose to construct a numerical model of combined subsurface magma flow and accumulation, magma degassing and volcano deformation. The magma flow model will be based on two-phase flow theory, with magma degassing incorporated from existing solubility and diffusivity formulations for magmatic volatiles. Volcano deformation will be modeled by coupling the flow model with well-established kinematic deformation models through mass conservation. Similarly, changes in magma composition will be estimated from mass balance considerations. Observations of surface deformation, gas emissions and changes in magma composition will constrain the time-dependent magma supply to each volcano. Model results will be used to test for correlative activity and assess potential mechanisms for dynamical coupling. In addition to testing this coupling hypothesis, the model can be used to interrogate the interplay between magma supply, storage and eruptive activity at each volcano, in particular at Kilauea, where the spatial and temporal frequencies of observations are high. In order to demonstrate the capabilities of this proposed modeling approach we will perform an exploration of the unknown parameters the model will include and all the available constraints. We will establish databases of the available geodetic, seismic, geochemical and gas observations, evaluate their completeness and reliability, and ascertain the model uncertainties and trade-offs, assessing the uniqueness of solutions and the statistics of the inverse problem.2013 marked the centennial of the Hawaiian Volcano Observatory located on Kilauea, Earth's most active, and near Mauna Loa, Earth's largest volcano. Both volcanoes are also two of the best and longest monitored volcanoes and have been instrumental to our understanding of the structure and dynamics of the Earth's mantle, the evolution of volcanic island chains, as well as basaltic volcanism in general. They are thought to be the archetypical manifestations of hot-spot volcanism, caused by a buoyantly upwelling mantle plume that undergoes partial melting at a few hundred kilometers depth beneath Hawaii. Upward percolation and accumulation of this melt results in spatially focused flow through the Hawaiian lithosphere, into magma chambers that are located at a few kilometers depth beneath each volcano, and from which volcanic eruptions are fed. Both volcanoes exhibit complex patterns of activity, including movement along large fault planes that underlie portions of each edifice, with the potential for large earthquakes, tsunamis and triggering of new eruptions. It has been suggested that magma accumulation at depth may itself facilitate movement on these faults. Whether these processes and feedbacks are confined to a single volcano or whether they may also affect the neighboring volcano remains uncertain. Future eruptions, especially from Mauna Loa, have significant potential to directly impact the main populations centers on the island of Hawaii, and an improved understanding of the processes at work within the volcanoes, and any dynamic link between then will benefit public safety through increased understanding of volcanoes and volcanic hazards. This project, which represents a collaborative effort between the University of Hawaii, Rice University and the US Geological Survey, is aimed at integrating a range of different types of observation and will, therefore, impact a number of different fields, including geodesy, seismology and geochemistry. Moreover, to maximize the public and educational impact, we will partner with New Media Arts classes from Kapiolani Community College.

火山之间的动态联系对长期和短期喷发预报具有重要意义。尽管这种联系被认为存在于某些火山系统中，但它仍然存在争议，潜在的机制也是如此。最近，基拉韦厄火山和莫纳罗亚火山的动力学耦合的可能性被提出，这是两个火山下面软流圈融化带压力扩散的结果，每个火山都从那里获得熔体，尽管来自不同的部分。为了验证这一假设，我们提出建立地下岩浆流动与聚集、岩浆脱气与火山变形相结合的数值模型。岩浆流动模型将基于两相流理论，并将岩浆脱气从现有的岩浆挥发物溶解度和扩散率公式中纳入。火山变形将通过质量守恒将流动模型与已建立的运动变形模型耦合来模拟。同样，岩浆组成的变化将从质量平衡的考虑来估计。对地表变形、气体排放和岩浆成分变化的观测将限制每座火山随时间变化的岩浆供应。模型结果将用于测试相关活动和评估动态耦合的潜在机制。除了验证这种耦合假设之外，该模型还可以用于询问每个火山的岩浆供应、储存和喷发活动之间的相互作用，特别是在基拉韦厄火山，那里的观测空间和时间频率都很高。为了证明这种建模方法的能力，我们将对模型将包括的未知参数和所有可用的约束进行探索。我们将建立现有的大地测量、地震、地球化学和天然气观测数据库，评估它们的完整性和可靠性，确定模型的不确定性和权衡，评估解的唯一性和反问题的统计性。2013年是夏威夷火山观测站成立100周年，该观测站位于地球上最活跃的基拉韦厄火山，靠近地球上最大的火山莫纳罗亚火山。这两座火山也是被监测时间最长、效果最好的火山，对我们了解地幔的结构和动力学、火山岛链的演化以及玄武岩火山作用都起到了重要作用。它们被认为是热点火山活动的典型表现，是由夏威夷地下几百公里深处浮力上涌的地幔柱部分融化造成的。这些熔融物向上渗透和积累，导致了夏威夷岩石圈的空间集中流动，进入位于每个火山下方几公里深处的岩浆室，火山喷发由此而来。两座火山都表现出复杂的活动模式，包括沿着每个建筑物部分下方的大型断层平面运动，有可能发生大地震、海啸和引发新的喷发。有人认为，岩浆在深部的聚集本身可能促进了这些断层上的运动。这些过程和反馈是否局限于单个火山，或者它们是否也可能影响邻近的火山，目前还不确定。未来的火山喷发，特别是莫纳罗亚火山的喷发，有可能直接影响夏威夷岛上的主要人口中心，对火山内部工作过程的进一步了解，以及它们之间的任何动态联系，将通过加深对火山和火山危害的了解，有利于公共安全。该项目代表了夏威夷大学、莱斯大学和美国地质调查局之间的合作努力，旨在整合一系列不同类型的观测，因此将影响许多不同的领域，包括大地测量学、地震学和地球化学。此外，为了最大限度地扩大公共和教育影响，我们将与卡皮奥拉尼社区学院的新媒体艺术课程合作。