Collaborative Research: Axial 3-D - Exploring the linkages between complex magma chamber structure, caldera dynamics, fluid pathways and hydrothermal venting

这项研究将获得水下轴状火山内部结构的高分辨率三维地图，该火山位于华盛顿州离岸约450公里处。这些数据将解决一个古老的问题：“火山到底是如何运作的？”轴向火山是获取地下岩浆房信息的理想地点，因为那里已经收集了许多其他数据。对轴向火山的地表特征进行了详细的测绘，并通过海洋观测倡议海底观测站（OOI）对火山进行了实时监测。获得岩浆房结构的图像将补充现有数据和OOI提供的实时数据，并使人们更好地了解轴向火山是如何工作的以及何时可能喷发。这项研究将促进人们对陆地和海底火山的了解。该项目为研究生和早期职业科学家提供培训。对数据的访问将是开放的。该项目将在R/V Marcus Langseth上完成对轴向火山和相关裂谷轴的全面三维多通道地震调查。此外，将收集8条15公里长的源-接收偏置二维反射剖面，以研究岩浆输送的深层结构。开发了一套复杂的地震成像工具，主要用于收集水下火山地形的多通道地震数据。这种算法方法已经在许多二维海洋环境中得到了应用，迄今为止在轴向火山上取得了最大的成功，在轴向火山上，岩浆室的顶部和底部已经被清晰地成像，以及上部地壳中连接岩浆室和附近热液喷口场的裂缝/管道。尽管取得了这样的成功，但轴向火山本质上是三维的，因此需要三维的方法来绘制岩浆管道系统与海底喷发动力学之间的复杂联系。例如，这种方法需要理解(1)三维断裂集如何与岩浆膨胀/退缩、裂陷和上地壳的重力扩张/崩塌相关联；(2)不同数量熔体/浆液的复杂岩浆体的几何形状和相互联系；(3)内部构造与海底热液场、熔岩流等观测资料的关系。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This study will obtain a high-resolution three-dimensional map of the internal structure of the underwater Axial Volcano, which is located about 450 km offshore of Washington State. These data will address the age-old question, "How do volcanoes really work?". Axial Volcano is an ideal location to obtain information on the underground magma chamber because a lot of other data have already been collected there. The surface features of Axial Volcano have been mapped in detail and the volcano is monitored in real-time through the Ocean Observatory Initiative Seafloor (OOI) Observatory. Obtaining an image of the magma chamber structure will complement existing data and the real-time data being provided by OOI, and allow a much better understanding of how Axial Volcano works and when it might erupt. This study will advance understanding of volcanoes both on land and underwater world wide. The project provides training for graduate students and early career scientists. Access to the data will be open. This project will complete a comprehensive 3-D multichannel seismic survey of Axial Volcano and associated rift axes aboard the R/V Marcus Langseth. In addition, eight 15-km-long source-receiver offset 2-D reflection profiles will be collected to look at deep-seated structure of magma delivery. A sophisticated set of seismic imaging tools focused on multichannel seismic data collected in underwater volcanic terrains has been developed. This algorithm approach has been used in a number of marine environments in 2-D, with the greatest success thus far at Axial Volcano, where the roof and floor of the underlying magma chamber have been clearly imaged, along with fractures/conduits in the upper crust connecting the magma chamber to nearby hydrothermal vent fields. Despite this success, Axial Volcano is inherently 3-D in nature, thus requiring a 3-D approach to map the complex connections between the magma plumbing system at depth with eruption dynamics at the seafloor. For example, this approach is needed to understand (1) how 3-D fracture sets are associated with magma inflation/withdrawal, rifting, and gravitational spreading/collapse in the upper crust; (2) the geometry and interconnection of complex magma bodies of varying amounts of melt/mush; (3) the relationship between internal structure and seafloor observables such as hydrothermal fields and lava flows.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.