Do volcanoes emit mercury? Understanding the behaviour of Hg in volcanic products.

火山会释放汞吗？

• 批准号: NE/C511180/2
• 负责人: David Pyle
• 金额: $ 20.82万
• 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: 2006
• 资助国家: 英国
• 起止时间: 2006 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FC511180%2F2
• 关键词: Do; volcanoes; emit; mercury; Understanding

This is a proposal to make some modern measurements of the quantities of volatile trace metals that are released to the atmosphere by volcanoes. Volcanic gases are often equated with sulphur. In fact, sulphur is just one component of volcanic gases; and in just the same way that sulphur from volcanoes can affect the atmosphere, so may other species. We wish to make measurements of mercury at volcanoes. Mercury is a curious element: in its elemental form (Hg(o)) it is very volatile, and is not usually very reactive. As a result, once it is in the atmosphere it will stay there for a long time (about a year), before eventually being removed. Mercury is of general interest because it is highly toxic [the cause, for example, of the condition described by the phrase 'mad as a hatter']. It has no 'useful' function for biological organisms, but becomes concentrated up the food chain. One of the big problems with the current understanding of natural mercury in the atmosphere is that the books don't balance: we don't know very well where mercury is released from; and we don't know where it ends up. It is possible that volcanoes contribute to this imbalance: some people think that volcanoes may release a large amount of mercury, perhaps as much as half of all natural emissions; others think that it is so small that it can be ignored. By making measurements close to the vent of two active volcanoes using some new and very sensitive equipment, we hope to resolve this problem: at the very least, we'll know how much mercury is released by steady, gentle activity at the world's persistently active volcanoes. These volcanoes might not hit the headlines, but our idea is that they are always there in the background, supplying gases and particles to the atmosphere. A second scientific problem that we want to look at is to understand how mercury escapes from molten lavas; in what forms it escapes (is it mainly in the gaseous form? or does some of it very quickly form very small particles? and if so , what happens to those particles?); and we want to use the way that mercury behaves to understand more about the extreme (hot, oxidising, chemically reactive) environment that is a volcanic plume. A third aspect that we also wish to study is to use the erupted rocks and minerals (at the same two volcanoes, Etna and Kilauea) to try and understand how mercury and its chemically-similar 'cousins' (metals including Cd, Zn, Cu) behave as a rock cools and crystallises. We think that mercury and cadmium, for example, should have a slight preference for certain minerals (clinopyroxene, feldspar), and that as a result their concentration in the melt won't change much during crystallisation, but may change a little by 'degassing'. We can test this idea using precise (laser) measurements of small samples of real rocks.

这是一项对火山释放到大气中的挥发性微量金属的数量进行现代测量的建议。火山气体常与硫磺等同起来。事实上，硫只是火山气体的一种成分；就像火山喷发的硫磺会影响大气一样，其他物种也可能会影响大气。我们希望测量火山上的汞含量。汞是一种奇怪的元素：它的单质形式（Hg(o)）极易挥发，通常不容易发生反应。因此，一旦它进入大气层，在最终被移除之前，它将在那里停留很长时间（大约一年）。汞引起了人们的普遍兴趣，因为它是剧毒的（例如，它是短语“疯得像个帽匠”所描述的病症的原因）。它对生物有机体没有“有用”的功能，而是集中在食物链的上游。目前对大气中天然汞的理解存在一个大问题，那就是数据并不平衡：我们不太清楚汞是从哪里释放出来的；我们不知道它最后会到哪里。火山可能造成了这种不平衡：有些人认为火山可能释放出大量的汞，可能相当于所有自然排放量的一半；其他人认为它是如此之小，可以忽略。通过使用一些新的、非常灵敏的设备在两座活火山的喷发口附近进行测量，我们希望能解决这个问题：至少，我们能知道世界上那些持续活跃的火山的稳定、温和的活动释放了多少汞。这些火山可能不会成为头条新闻，但我们的想法是，它们一直在背景中，向大气提供气体和颗粒。我们想要研究的第二个科学问题是了解汞是如何从熔岩中逸出的；它以什么形式逸出（主要是气态吗？）或者其中一些会很快形成非常小的粒子？如果是这样，这些粒子会发生什么变化？)；我们想利用汞的行为方式来更多地了解火山柱的极端（高温、氧化、化学反应）环境。我们还希望研究的第三个方面是利用喷发的岩石和矿物（在同样的两座火山，埃特纳火山和基拉韦厄火山），试图了解汞及其化学相似的“表亲”（包括Cd、Zn、Cu等金属）在岩石冷却和结晶时的行为。例如，我们认为汞和镉应该对某些矿物（斜辉石、长石）有轻微的偏好，因此它们在熔体中的浓度在结晶过程中不会发生太大变化，但在“脱气”过程中可能会发生一点变化。我们可以用精确的（激光）测量真实岩石的小样本来验证这个想法。

项目成果

Melt inclusions track pre-eruption storage and dehydration of magmas at Etna

• DOI: 10.1130/g30040a.1
• 发表时间: 2009-06-01
• 期刊: GEOLOGY
• 影响因子: 5.8
• 作者: Collins, S. J.;Pyle, D. M.;Maclennan, J.
• 通讯作者: Maclennan, J.

Major and trace element distributions around active volcanic vents determined by analyses of grasses: implications for element cycling and bio-monitoring

通过草分析确定活火山口周围的主要和微量元素分布：对元素循环和生物监测的影响

• DOI: 10.1007/s00445-010-0374-7
• 发表时间: 2010
• 期刊: Bulletin of Volcanology
• 影响因子: 3.5
• 作者: Martin R