The chemical behaviour of sulphur in magmas at high temperature and pressure

高温高压下岩浆中硫的化学行为

• 批准号: NE/W000660/1
• 负责人: Bernard Wood
• 金额: $ 53.88万
• 依托单位: University of Oxford
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2022
• 资助国家: 英国
• 起止时间: 2022 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FW000660%2F1
• 关键词: chemical; behaviour; sulphur; magmas; temperature

The aim of this project is to develop a clear understanding of the behaviour of the element sulphur in volcanoes and in the gases which are expelled from volcanoes during and prior to volcanic eruptions. Volcanoes have important effects on both their local and global environments. In the global context they emit large clouds of ash and polluting gases particularly sulphur in the form of sulphur dioxide. Both ash and sulphur dioxide have the effect of cooling the atmosphere. During the 1991 eruption of Mt Pinatubo in the Philippines, for example 18 million tons of sulphur dioxide were emitted and cooling of the atmosphere at ground level lasted 1-3 years. A more extreme example is the eruption of Mt Tambora (Indonesia) in 1815. This produced 120 million tons of sulphur dioxide which led to the "year without summer" of 1816. In the Northern Hemisphere in 1816 crops failed, livestock died and many people starved. Such eruptions with similar or greater climatic effects can be expected episodically in the future despite the long-term trend of increasing global temperatures. Understanding how and why sulphur dioxide is emitted during volcanic activity is, therefore, central to this project. Despite the environmental importance of such emissions from volcanoes it is surprising that there is little information available on the extent to which sulphur dioxide dissolves in volcanic liquids (lavas) prior to and during eruption. One of the aims of the project is therefore to determine how much of the gas is dissolved in lavas at high pressures deep in the Earth's crust and how much is degassed to the atmosphere as the lava moves from deep in the crust to just underneath the volcano. This will enable geologists to connect the amounts of lava erupted as liquid and ash to the anticipated climatic effects in the form of sulphur dioxide emitted.A second aim of the project is to determine the conditions under which economically important deposits of sulphur-rich ore minerals occur in association with volcanic activity. Geologists know the kinds of environment in which these deposits occur, but there are still unresolved questions about the depths at which the ore minerals become stable. Are, for example, economically important deposits more likely to be found if the crust is thin or thick in the area of interest? By performing experiments at different pressures, simulating different crustal thicknesses, this project aims to answer that question.

该项目的目的是对火山和火山喷发之前和之前从火山排出的气体中硫的行为进行清晰的了解。火山对其本地和全球环境都有重要影响。在全球背景下，它们散发出巨大的灰烬和污染气体，尤其是硫磺二氧化硫的形式。灰分和二氧化硫都具有冷却大气的作用。在1991年菲律宾Pinatubo山爆发期间，例如，发出了1800万吨二氧化硫，地面上的大气冷却持续了1 - 3年。一个更极端的例子是1815年印度尼西亚山（印度尼西亚）的爆发。这产生了1.2亿吨二氧化硫，导致了1816年的“没有夏天”的“一年”。1816年的北半球作物失败了，牲畜死了，许多人死了，许多人饿死了。尽管长期升高了全球温度，但这种爆发具有相似或更大的气候影响。因此，了解在火山活动期间如何发出二氧化硫是该项目的核心。尽管火山的这种排放具有环境的重要性，但令人惊讶的是，在喷发之前和期间，二氧化硫在火山液体（LAVA）中溶解的程度很少。因此，该项目的目的之一是确定在地壳深处高压的熔岩中溶解了多少气体，以及随着熔岩从地壳的深处移动到火山下方，将多少气体溶解在大气中。这将使地质学家能够以液体和灰分爆发的熔岩量与预期的气候作用，以发射的二氧化硫的形式连接到预期的气候作用。该项目的第二个目的是确定与火山活性相关的硫富矿石矿物质经济上重要沉积物的条件。地质学家知道这些沉积物发生的环境种类，但是关于矿石矿物质稳定的深度仍未解决的问题。例如，如果地壳在感兴趣的区域薄或厚，那么在经济上重要的沉积物是否更有可能发现？通过以不同的压力进行实验，模拟不同的地壳厚度，该项目旨在回答该问题。

项目成果

Sulfur oxidation state and solubility in silicate melts

硫的氧化态和在硅酸盐熔体中的溶解度

• DOI: 10.1007/s00410-023-02033-9
• 发表时间: 2023
• 期刊: Contributions to Mineralogy and Petrology
• 影响因子: 3.5
• 作者: Boulliung J