Collaborative Research: Heterogeneous Bubble Dynamics in Volcanic Conduits

合作研究：火山管道中的非均质气泡动力学

• 批准号: 1250451
• 负责人: Helge Gonnermann
• 金额: $ 12.98万
• 依托单位: William Marsh Rice University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-01-01 至 2014-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1250451&HistoricalAwards=false
• 关键词: Collaborative; Research; Heterogeneous; Bubble; Dynamics

Volcanic eruptions can have significant impact on life, infrastructure, commerce and climate. Erupting magma is a mixture of hot rock fragments (formerly magma), such as volcanic ash, and volcanic gases that are transported to surface as bubbles within the erupting magma. Bubbles may both, confine magmatic gases potentially resulting in large excess gas pressures, or they may facilitate syneruptive gas loss by forming permeable networks during bubble coalescence. Consequently, bubbles play a crucial role in a feedback with magma ascent rate and affect the style and explosive intensity of eruptions.This project will further our quantitative understanding of the various processes that affect bubbles and magmatic gases during volcanic eruptions. We will develop a new bubble-scale numerical model for bubble growth, deformation and coalescence. The model will be calibrated to laboratory experiments that are specifically designed to facilitate the integration of empirical data. The bubble-scale model will then be coupled with a multiphase conduit flow model to address problems such as (1) the spatiotemporal evolution of gas pressure in an erupting magma with a polydisperse bubble size distribution; (2) the implications for magma fragmentation; (3) bubble coalescence during shear deformation of the erupting magma; (4) open-system gas loss by permeable flow through coalesced bubbles; and (5) shear localization within the ascending magma.

火山爆发可能对生命、基础设施、商业和气候产生重大影响。喷发的岩浆是热的岩石碎片（以前的岩浆），如火山灰和火山气体的混合物，这些气体在喷发的岩浆中以气泡的形式被输送到地表。气泡既可以限制岩浆气体，潜在地导致大的过量气体压力，也可以通过在气泡聚结期间形成可渗透网络来促进同生喷发气体损失。因此，气泡在反馈岩浆上升速率中起着至关重要的作用，并影响喷发的方式和爆炸强度。本项目将进一步定量了解火山喷发过程中影响气泡和岩浆气体的各种过程。我们将发展一个新的气泡尺度的气泡生长，变形和合并的数值模型。该模型将根据专门设计用于促进经验数据整合的实验室实验进行校准。然后将气泡尺度模型与多相导管流模型相结合，以解决以下问题：（1）具有多分散气泡尺寸分布的喷发岩浆中气体压力的时空演变;（2）岩浆破碎的含义;（3）喷发岩浆剪切变形期间气泡的聚结;（4）通过聚结气泡的渗透流造成的开放系统气体损失;（5）气泡尺度模型与多相导管流模型相结合。（5）上升岩浆内部的剪切局部化。