Testing eruption-triggering mechanisms at Axial Caldera using statistical data assimilation

全世界数百万人生活在活火山系统的阴影下。在美国，加州、太平洋西北部、阿拉斯加和夏威夷的活火山由地面仪器和卫星观测监测，以便为当地社区提供潜在喷发和危害的早期预警。在陆地上，全球定位系统和卫星观测可以发现火山膨胀，并提供动荡的早期预警。然而，地表变形和喷发之间的联系仍然不清楚。该项目将解决位于俄勒冈州海岸外胡安德富卡山脊的海底轴向火山的这一联系。与陆地上的火山不同，中轴火山的变形似乎与喷发密切相关。尽管如此，轴火山的最终喷发触发机制仍然未知。跨越三个喷发周期的三十年观测将提供必要的数据，以“后投”过去的喷发轴，并寻找特定的喷发前兆的变形信号导致喷发。轴向火山是一个理想的天然实验室，以测试喷发触发机制的假设和变形与活火山喷发之间的联系。 该项目支持培养博士。在这个项目中，统计数据同化技术将被用于将联合收割机地面变形观测与轴向火山的有限元模型相结合，以产生1998年，2011年和2015年爆发的后模型，并调查可能引发轴向火山爆发的机制。调查的第一步将测试喷发前兆和触发机制。第二步将制定一种方法，利用海洋观测倡议轴向区域节点的近实时数据，预测轴向火山未来的动荡。这些进展将为轴向火山系统的演化提供重要的见解。轴向火山是唯一一个成功的基于变形的喷发预测系统，它可以为理解火山喷发是如何触发的提供一个重要的缺失环节。

Millions of people around the world live in the shadows of active volcanic systems. In the United States, active volcanoes in California, the Pacific Northwest, Alaska, and Hawaii are monitored both by ground based instruments and satellite observations to provide early warning of potential eruptions and hazards for local communities. On land, GPS and satellite observations can detect volcano inflation and provide early warning of unrest. However, the link between surface deformation and eruption remains unclear. This project will address this link at the submarine Axial Volcano located on the Juan de Fuca Ridge off of the coast of Oregon. Unlike volcanoes on land, deformation of Axial Volcano appears to be closely linked to eruption. Still, the ultimate eruption triggering mechanism at Axial Volcano remains unknown. Three decades of observations spanning three eruption cycles will provide the data necessary to 'hind-cast' past eruptions at Axial and look for specific eruption precursors in the deformation signal leading up to eruption. Axial Volcano is an ideal natural laboratory to test hypotheses for eruption triggering mechanisms and the link between deformation and eruption at active volcanoes. This project supports the training of a Ph.D. student.In this project statistical data assimilation techniques will be used to combine ground deformation observations with finite element models of Axial Volcano to produce hind casts of the 1998, 2011, and 2015 eruptions and investigate what mechanisms might have triggered eruption of Axial. The first step in the investigation will test eruption precursors and triggering mechanism. The second step will develop a method for utilizing data from the Ocean Observatory Initiative Axial Regional Node in near-real time to forecast future unrest at Axial Volcano. These advancements will provide critical insight into the evolution of the Axial volcanic system. Axial Volcano is the only system with a successful deformation based eruption prediction and it could provide an important missing link for understanding how eruptions are triggered at volcanoes.