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

世界各地有数百万人生活在活跃的火山系统的阴影下。在美国，加利福尼亚州、太平洋西北部、阿拉斯加和夏威夷的活火山通过地面仪器和卫星观测进行监测，为当地社区提供潜在喷发和危险的早期预警。在陆地上，GPS和卫星观测可以检测到火山膨胀，并提供动乱的早期预警。然而，地表变形和喷发之间的联系仍不清楚。该项目将在位于俄勒冈州海岸外胡安德富卡山脊的海底Axial火山解决这一问题。与陆地上的火山不同，轴心火山的变形似乎与喷发密切相关。尽管如此，Axial火山最终的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，以便在Axial‘预测’过去的喷发，并在导致喷发的形变信号中寻找特定的喷发前兆。轴向火山是检验活火山喷发触发机制和变形与喷发之间联系的理想自然实验室。该项目支持博士研究生的培养。在该项目中，将使用统计数据同化技术将地面变形观测与Axial火山的有限元模型相结合，生成1998年、2011年和2015年的喷发后预报，并调查可能引发Axial喷发的机制。调查的第一步将测试喷发前兆和触发机制。第二步将开发一种方法，利用海洋天文台倡议轴心区域节点的数据，近乎实时地预测轴心火山未来的动荡。这些进展将提供对轴向火山系统演化的重要洞察。轴向火山是唯一一个成功地进行了基于形变的喷发预测的系统，它可能为理解火山喷发是如何触发的提供了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.