Bubble dynamics during volcanic eruptions: in situ measurements and modelling of physical processes of a rising and exploding gas slug

火山喷发期间的气泡动力学：气段塞上升和爆炸物理过程的现场测量和建模

• 批准号: 13799595
• 负责人: Professor Dr. Matthias Hort
• 金额: --
• 依托单位: Institut für Geophysik (IfG)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2006
• 资助国家: 德国
• 起止时间: 2005-12-31 至 2014-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/13799595?language=en
• 关键词: Bubble; dynamics; during; volcanic; eruptions

During the initial two years funding of this research we collected a 16 days long multidisciplinary data set at Yasur volcano, Vanuatu, that includes seismological and acoustic data, infrared video footage, as well as Doppler radar measurements to quantify eruption dynamics, and DOAS measurements for SO2 flux estimation. During this time a total of about 26000 eruptions were observed and initial data processing indicated a transition in eruption style from explosive nearly ash free eruptions to very ash rich plumes and back to nearly ash free eruptions. In the frame of this proposal we will explore the physics behind this change in eruption style using our multidisciplinary data set. In particular we will combine the processed seismic and acoustic data with the radar data to verify which vent of Yasur volcano was active and determine at what depth below the vent exit the magma level in the conduit is located. Exploiting the radar data we will determine the kinetic energy released during each single explosion and from that determine either bubble overpressure or gas slug volume, while the acoustic and seismic data will give us evidences for the seismic and acoustic energy release. This will lead to a more complete understanding of the energy budget at an active volcano. The radar data will also allow us to define different eruption types and using a neuronal network we will then classify all recorded events. These different processing steps will help to improve current models for eruption dynamics.

在资助这项研究的最初两年中，我们在瓦努阿图亚苏尔火山收集了为期 16 天的多学科数据集，其中包括地震和声学数据、红外视频片段以及用于量化喷发动态的多普勒雷达测量值和 DOAS 测量值SO2 通量估算。在此期间，总共观察到约 26000 次喷发，初步数据处理表明喷发类型从爆发性几乎无灰喷发转变为富含火山灰的羽状喷发，然后又回到几乎无灰喷发。在该提案的框架内，我们将使用我们的多学科数据集探索喷发类型变化背后的物理原理。特别是，我们将处理后的地震和声学数据与雷达数据相结合，以验证亚苏尔火山的哪个喷口处于活动状态，并确定管道中的岩浆液位位于喷口出口下方的深度。利用雷达数据，我们将确定每次爆炸期间释放的动能，并从中确定气泡超压或气段塞体积，而声学和地震数据将为我们提供地震和声学能量释放的证据。这将有助于更全面地了解活火山的能量预算。雷达数据还允许我们定义不同的喷发类型，然后使用神经网络对所有记录的事件进行分类。这些不同的处理步骤将有助于改进当前的喷发动力学模型。