Seismo-Acoustic Dynamics of Silicic Dome Eruptions

硅质穹顶喷发的地震声动力学

• 批准号: 0337462
• 负责人: Jonathan Lees
• 金额: $ 14.82万
• 依托单位: University of North Carolina at Chapel Hill
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-01-01 至 2006-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0337462&HistoricalAwards=false
• 关键词: Seismo; Acoustic; Dynamics; Silicic; Dome

The investigators propose a study of two Andean volcanoes, Guagua Pichincha and Tungurahua, Ecuador, because they exhibit relatively frequent explosive events (both pyroclastic and phreato-magmatic) and offer unparalleled access for field study. Activity at Pichincha is an analogue for active volcanism at: Unzen, Merapi, Bezmianny, and Monserrat. Tungurahua is extremely hazardous due to its steep elevation and danger posed to the city of Banos. The project is aimed at field observations and developing new models for silicic volcanism in general and these two volcanoes specifically.To understand the controlling features of volcanic degassing at silicic domes new instrumentation, including broadband seismic and infrasonic acoustic sensors will be installed to monitor the Strombolian-type explosion activity. The technology required to accomplish high fidelity observations, including hardware and software, will be transferred to Ecuadorian Colleagues at the Instituto Geofisica in Quito. Elastic and acoustic energy radiation recorded with arrays of infrasonic microphones and broad-band seismometers will be used to assess the explosive energy release, relative energy partitioning into the ground and atmosphere, and explosion source location. Digitized video records will be used to calibrate infrasound generation with gas plume ejection velocities and verify source time origin and locations. Physical models of explosive degassing at domes will be developed and compared to lower-viscosity, open-vent magmatic systems (Stromboli, Karymsky, Arenal, Erebus), so that infrasonic and seismic tools can be used to remotely predict degassing behavior for all types of volcanic explosions. The major impact of this proposal will be 1) the development of new volcano explosion models applied to previously unexplored volcanic activity, 2) new observations of seismo/acoustic signals at hazardous volcanoes in Ecuador, and 3) establishment of a strong collaboration between Ecuadorian and U.S. researchers on active volcanic hazard reduction, 4) assessment of hazard prior to large collapse events on dangerous volcanoes.This project is co-sponsored by the Americas Program in the Office Of International Science And Engineering.

研究人员提议对厄瓜多尔的两座安第斯火山（瓜瓜皮钦查火山和通古拉瓦火山）进行研究，因为它们表现出相对频繁的爆发事件（火山碎屑和火山岩浆），并为实地研究提供了无与伦比的途径。 皮钦查的活动类似于云仙、默拉皮、贝兹米安尼和蒙塞拉特的活火山活动。 通古拉瓦海拔陡峭，对巴尼奥斯市构成危险，极其危险。 该项目旨在对硅质火山活动（特别是这两座火山）进行现场观测并开发新模型。为了了解硅质穹顶火山脱气的控制特征，将安装包括宽带地震和次声波传感器在内的新仪器来监测斯特龙博利安型爆炸活动。 完成高保真观测所需的技术，包括硬件和软件，将转移给基多地理研究所的厄瓜多尔同事。 使用次声麦克风和宽带地震仪阵列记录的弹性和声能辐射将用于评估爆炸能量释放、地面和大气中的相对能量分配以及爆炸源位置。 数字化视频记录将用于校准次声波的气体羽流喷射速度，并验证源时间起源和位置。 将开发圆顶爆炸脱气的物理模型，并将其与低粘度、开放式岩浆系统（Stromboli、Karymsky、Arenal、Erebus）进行比较，以便次声和地震工具可用于远程预测所有类型火山爆炸的脱气行为。该提案的主要影响将是：1）开发新的火山爆发模型，应用于以前未探索的火山活动，2）对厄瓜多尔危险火山的地震/声学信号进行新的观测，3）厄瓜多尔和美国研究人员在减少活跃火山灾害方面建立强有力的合作，4）在危险火山发生大型塌陷事件之前评估危险。 由国际科学与工程办公室美洲项目共同赞助。