MAGMA RHEOLOGY and VOLCANIC ERUPTION: Experiments and Models

岩浆流变学和火山喷发：实验和模型

• 批准号: 820-2013
• 负责人: Russell, James
• 金额: $ 4.15万
• 依托单位: University of British Columbia
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2017
• 资助国家: 加拿大
• 起止时间: 2017-01-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=633698
• 关键词: MAGMA; RHEOLOGY; VOLCANIC; ERUPTION; Experiments

This research program comprises 2 distinct but complementary themes in volcanology.1) A Model for Silicate Melt Viscosity: Redux. Viscosity is the most important physical property governing transport and eruption of magma. In 2008, we published the "GRD model" for predicting the viscosity of natural hydrous silicate melts. The model is widely accepted as the best available but a second generation model is critical due to the ever-increasing diversity of geoscientists that use the model. The current limitations include: i) the model does not capture the low-T viscosity of many rhyolite melts; ii) we do not account for dissolved CO2; iii) iron is a treated as a single species (i.e. FeO_Total) whereas silicate melts contain both Fe3+ and Fe2+; iv) we do not account for the effects of pressure (P); and v) the model is empirical and this limits its ability to predict derivative physical-chemical properties. I propose to release a second generation model to eliminate these limitations. The resulting model will capture virtually all silicate melts found on Earth and other planets and will have a stronger theoretical basis allowing for prediction of other thermochemical properties.2) Rock Mechanics of Volcanic Systems: Experiments and Models. Magma rheology is key to understanding and predicting the styles and intensities of volcanic eruption. The Rock Mechanics of Volcanic Systems is a new, dynamic, and highly competitive area of research; it lies at the interface between the well-established fields of Rock Mechanics and Experimental Volcanology. The goal of this experimentation is to establish the rheological properties of volcanic materials at the conditions attending volcanic eruption. These data are used to build constitutive equations that predict the flow of natural magmas as a function of stress, strain-rate, temperature and crystal content. These constitutive equations for magma rheology are the key to more sophisticated and accurate modelling of volcanic eruptions.

该研究计划包括2个不同但互补的主题。1）硅酸盐熔体粘度的模型：redux。粘度是管理岩浆运输和喷发的最重要的物理特性。 2008年，我们发表了“ GRD模型”，用于预测天然硅酸盐熔体的粘度。该模型被广泛接受为最佳可用，但是由于使用该模型的地球科学家的多样性不断增加，第二代模型至关重要。当前的局限性包括：i）该模型没有捕获许多流纹岩熔体的低T粘度； ii）我们不考虑溶解的二氧化碳； iii）铁是一种被视为单个物种（即feo_total），而硅酸盐熔体含有Fe3+和Fe2+； iv）我们不考虑压力的影响（p）； v）该模型是经验的，这限制了其预测衍生物理化学特性的能力。我建议发布第二代模型以消除这些局限性。所得模型几乎将捕获地球和其他行星上发现的所有硅酸盐融化，并具有更强的理论基础，允许预测其他热化学特性。2）火山系统的岩石力学：实验和模型。岩浆流变学是理解和预测火山喷发的风格和强度的关键。火山系统的岩石力学是一个新的，动态且竞争激烈的研究领域。它位于岩石力学和实验火山学领域的界面。该实验的目的是在火山喷发的条件下建立火山材料的流变特性。这些数据用于构建组成方程，以预测自然岩浆的流动，这是应力，应变率，温度和晶体含量的函数。这些岩浆流变学的本构方程是对火山喷发进行更复杂和准确建模的关键。