EAR-PF Investigating Volcanic Explosion Directivity Using Aerial Infrasound Observations with UAVs

EAR-PF 利用无人机空中次声观测研究火山爆炸方向性

• 批准号: 1952392
• 负责人: Alexandra Iezzi
• 金额: $ 17.4万
• 依托单位: Iezzi, Alexandra Michelle
• 依托单位国家: 美国
• 项目类别: Fellowship Award
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-08-01 至 2022-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1952392&HistoricalAwards=false
• 关键词: EAR; PF; Investigating; Volcanic; Explosion

Dr. Alexandra Iezzi has been granted an NSF EAR Postdoctoral Fellowship to carry out research and educational activities at the University of California Santa Barbara under the mentorship of Professor Robin Matoza. Infrasound sensors measure low-frequency acoustic waves (below the limit of human hearing) and provide a detailed means to monitor and characterize explosive sources such as those caused by volcanic eruptions. However, these sensors are usually placed on the Earth's surface, providing only a limited sampling of the acoustic radiation pattern and directionality of volcanic explosions creating a bias in how acoustic sources are characterized. This project addresses this issue by using a novel approach of collecting infrasound data with sensors aboard multiple unmanned aerial vehicles (UAVs) in addition to traditional sensor deployments on the ground. Our sensor platform and measurements will increase our understanding of acoustic directivity at the frequently active Yasur volcano, in Vanuatu and for explosive sources in general. The research proposed here has the potential to revolutionize the way active volcanoes are monitored using infrasound instrumentation aimed at providing unique information on explosion dynamics. The new techniques proposed will allow infrasound sensors to be deployed both in the air and on the ground close to the eruption, so that a volcanic source is understood better with significantly reduced risk exposure to field personnel. This project is a proof-of-concept study of UAV-based infrasound deployments that can extend data collection to previously unreachable locations near active volcanoes and anthropogenic explosion sources around the world. The UAV-mounted infrasound sensors will record data from unique angles, allowing for acoustic source inversion methods that account for the effects of topography to constrain the directional radiation pattern of explosions in a way not previously possible. By following these methods, we will also improve the calculation of the mass flow rate, which is an invaluable parameter for monitoring. The infrasound observations will be validated with ballistic trajectories determined from multiple cameras deployed around the crater rim, which we assume to be similar to the directionality of ash, gas, and steam emissions that may present harm to those near the volcano. Configuring UAV-mounted infrasound sensors in a vertical line above one of the crater rim stations will, for the first time, allow us to investigate the precise vertical location of the infrasonic source. Finally, we will create a prototype and test a UAV infrasound sensor deployment where the sensor is flown to an inaccessible area, dropped off, and retrieved by the UAV. This technique can be applied for future monitoring during times of eruption crises. As part of the broader impacts of this project Dr. Iezzi will teach a reading seminar course and design a demonstration mimicking the usage of UAVs around Yasur volcano entitled “trashcano”, which is sure to catch middle-school students’ interest. Outreach activities include a photo-journal from Yasur volcano to share with local teachers and thus expanding outreach educational efforts.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.

Alexandra Iezzi博士已获得NSF博士后奖学金，在Robin Matoza教授的指导下在加州圣巴巴拉大学开展研究和教育活动。次声传感器测量低频声波（低于人的听力极限），并提供详细的手段来监测和确定火山爆发等爆炸源的特征。然而，这些传感器通常放置在地球表面，仅提供有限的火山爆发的声辐射模式和方向性的采样，从而在如何确定声源的特征方面产生偏差。该项目通过使用一种新的方法来解决这个问题，该方法除了在地面上部署传统的传感器外，还使用多个无人机（UAV）上的传感器收集次声数据。我们的传感器平台和测量将增加我们对瓦努阿图经常活跃的亚苏尔火山以及一般爆炸源的声学方向性的理解。这里提出的研究有可能彻底改变使用次声仪器监测活火山的方式，目的是提供有关爆炸动力学的独特信息。拟议的新技术将使次声传感器能够部署在空中和靠近火山爆发的地面上，以便更好地了解火山源，大大减少实地人员面临的风险。该项目是基于无人机的次声部署的概念验证研究，可以将数据收集扩展到世界各地的活火山和人为爆炸源附近以前无法到达的位置。无人机安装的次声传感器将从独特的角度记录数据，从而允许考虑地形影响的声源反演方法以以前不可能的方式限制爆炸的定向辐射模式。通过这些方法，我们还将改进质量流率的计算，这是一个非常宝贵的监测参数。次声观测将通过火山口边缘部署的多个摄像机确定的弹道轨迹进行验证，我们假设这些弹道轨迹与火山灰，气体和蒸汽排放的方向性相似，可能会对火山附近的人造成伤害。将无人机安装的次声传感器配置在一个陨石坑边缘站上方的垂直线上，将首次使我们能够调查次声源的精确垂直位置。最后，我们将创建一个原型，并测试无人机次声传感器的部署，传感器被飞行到一个不可访问的区域，下降，并由无人机检索。这种技术可用于未来火山爆发危机期间的监测。作为该项目更广泛影响的一部分，Iezzi博士将教授一门阅读研讨课程，并设计一个模拟亚苏尔火山周围无人机使用的演示，名为“trashcano”，这肯定会引起中学生的兴趣。外展活动包括一个来自Yasur火山的摄影杂志，与当地教师分享，从而扩大外展教育工作。该奖项反映了NSF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。

项目成果

Narrow-Band Least-Squares Infrasound Array Processing

窄带最小二乘次声阵列处理

• DOI: 10.1785/0220220042
• 发表时间: 2022
• 期刊: Seismological Research Letters
• 影响因子: 3.3
• 作者: Iezzi, Alexandra M.;Matoza, Robin S.;Bishop, Jordan W.;Bhetanabhotla, Sneha;Fee, David
• 通讯作者: Fee, David

Synthetic Evaluation of Infrasonic Multipole Waveform Inversion

次声多极波形反演综合评价

• DOI: 10.1029/2021jb023223
• 发表时间: 2022
• 期刊: Journal of Geophysical Research: Solid Earth
• 作者: Iezzi, Alexandra M.;Matoza, Robin S.;Fee, David;Kim, Keehoon;Jolly, Arthur D.
• 通讯作者: Jolly, Arthur D.

High-rate very-long-period seismicity at Yasur volcano, Vanuatu: source mechanism and decoupling from surficial explosions and infrasound

瓦努阿图亚苏尔火山的高频率超长周期地震活动：震源机制以及与地表爆炸和次声的解耦

• DOI: 10.1093/gji/ggab533
• 发表时间: 2022
• 期刊: Geophysical Journal International
• 影响因子: 2.8
• 作者: Matoza, Robin S.;Chouet, Bernard A.;Jolly, Arthur D.;Dawson, Phillip B.;Fitzgerald, Rebecca H.;Kennedy, Ben M.;Fee, David;Iezzi, Alexandra M.;Kilgour, Geoff N.;Garaebiti, Esline
• 通讯作者: Garaebiti, Esline

Evidence for near-source nonlinear propagation of volcano infrasound from Strombolian explosions at Yasur Volcano, Vanuatu

• DOI: 10.1007/s00445-022-01552-w
• 发表时间: 2022-03
• 期刊: Bulletin of Volcanology
• 影响因子: 3.5
• 作者: S. Maher;R. Matoza;A. Jolly;C. de Groot-Hedlin;K. Gee;D. Fee;A. Iezzi

Volcano infrasound: progress and future directions

• DOI: 10.1007/s00445-022-01544-w
• 发表时间: 2022-04
• 期刊: Bulletin of Volcanology
• 影响因子: 3.5
• 作者: L. M. Watson;A. Iezzi;L. Toney;S. Maher;D. Fee;Kathleen F. McKee;H. Ortiz;R. Matoza;J. Gestrich;J. Bishop;Alex J. C. Witsil;Jacob F. Anderson;Jeffrey B. Johnson