Physical Properties of Bubble- and Crystal-Bearing Melts and their Implications for Eruption Dynamics: Theoretical, Experimental and Field-Based Studies

含气泡和晶体熔体的物理性质及其对喷发动力学的影响：理论、实验和现场研究

• 批准号: 0608885
• 负责人: Michael Manga
• 金额: $ 17.38万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-07-01 至 2010-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0608885&HistoricalAwards=false
• 关键词: Physical; Properties; Bubble; Crystal; Bearing

Inside volcanoes, the formation of bubbles (vesiculation), the breaking of magma into discrete pieces (fragmentation), and the loss of gas in bubbles from ascending magma (degassing) are the key processes that control the dynamics of the erupting magma. The ultimate goal of this project is to understand how these processes interact and are reflected in the features of a volcanic eruption and the products it produces.It is proposed to perform experimental and numerical studies of eruption dynamics and modeling of eruption products in order to understand what controls whether an eruption will be explosive or effusive. The research tasks will include measurements of volatile contents and gradients in obsidian from both explosive and effusive eruption to determine the timescales for vesiculation, degassing and fragmentation. In addition, the team will develop conduit models to understand the competing and interacting effects of flow, degassing, and changes in magma rheology. It is planned to continue experimental studies of the effects of bubbles and crystals or the rheology of suspensions to allow for better models of rheology to be included in conduit flow simulations.This project provides graduate training for three students, supports international collaboration, and interaction with a new user facility at the Advanced Light Source. Because the project is aimed at understanding the controls on eruption style and the relationship between conduit processes and features of erupted materials (texture, volatile content), results will provide a better basis for estimating volcanic hazard, both from a modeling perspective, and from measurements on historic and prehistoric deposits.

在火山内部，气泡的形成（泡化）、岩浆破碎（碎裂）以及上升的岩浆中气泡中的气体损失（脱气）是控制岩浆喷发动力学的关键过程。该项目的最终目标是了解这些过程如何相互作用，并反映在火山喷发及其产生的产物的特征中。我们建议进行喷发动力学和喷发产物建模的实验和数值研究，以了解是什么控制了喷发是爆发性的还是渗出性的。研究任务将包括测量爆炸和喷涌喷发中黑曜石的挥发性含量和梯度，以确定泡化、脱气和破碎的时间尺度。此外，该团队将开发管道模型，以了解流动、脱气和岩浆流变学变化的竞争和相互作用。计划继续对气泡和晶体的影响或悬浮液的流变学进行实验研究，以便在管道流动模拟中纳入更好的流变学模型。该项目为三名学生提供研究生培训，支持国际合作，并与先进光源的新用户设施进行互动。由于该项目旨在了解喷发方式的控制因素以及管道过程与喷发物质特征（质地、挥发物含量）之间的关系，因此从建模角度以及从历史和史前沉积物的测量结果来看，结果将为估计火山危害提供更好的基础。