Selenium in Volcanic Environments (SELVES)

火山环境中的硒 (SELVES)

• 批准号: NE/X010120/1
• 负责人: Marie Edmonds
• 金额: $ 10.21万
• 依托单位: University of Cambridge
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FX010120%2F1
• 关键词: Selenium; Volcanic; Environments; SELVES

Selenium (Se) is a naturally-occurring metalloid that is nutritionally-required in small amounts but can become toxic at concentrations only twice recommended doses. UK soils are typically Se-deficient and require supplementation, but in volcanic regions and in soils overlying phosphate or organic-rich shales Se may be present in excess, representing a significant health challenge. Selenium is of critical importance in photovoltaics, glass production, fertilisers and batteries; Se demand is projected to rise 5-10 times by 2050. Volcanoes dominate the natural sources of Se (and its chemical 'twin', sulfur) to the environment. Due to its extreme volatility Se is enriched in volcanic gases and aerosol and in hydrothermal fluids, from which Se is deposited in porphyries and mined as a by-product with copper. Up to now, due to the technical challenges involved with sampling Se in volcanic gases and analysing it precisely in volcanic rocks, our quantitative understanding of volcanic Se is extremely limited. We propose the launch of a set of new studies of Se geochemistry (and that of other environmentally-important trace volatile metals) which take advantage of the recent development of using unoccupied aerial vehicles to sample high temperature gases; and new, precise analytical protocols for Se measurements. We have a range of suitable samples in hand already, from a diverse suite of samples of lavas, and gas/aerosol, collected by the investigators during recent explosive basaltic eruptions in a range of settings (hotspot: Cumbre Vieja, La Palma, 2021; Kilauea, USA, 2018, Fagradalsfjall, Iceland, 2021; subduction zone: Ambrym Volcano, Vanuatu, 2018; and Villarrica, Chile, 2018). We will quantify the flux of outgassing Se from each eruption, along with sulfur, and the controls on it; and establish in what chemical, bioavailable form Se is delivered to the surface environment via eruptions. The successful achievement of these objectives provides the basis for larger, integrative, high impact studies focussed on heavy metals (e.g. mercury, thallium and lead, as well as Se) delivered to the surface environment by volcanic activity, their environmental fate, biological uptake, including the competing effects of Se and S uptake by plants and incorporation into groundwater, both in the modern-day and in the history of our planet. This study lays the groundwork for improved hydrothermal models of Se partitioning into porphyry deposits and sustainable and efficient Se ore resource utilisation. This project explores the frontiers of a wide-ranging topic with impacts across the NERC remit through the nexus of health, environment and economy.

硒(Se)是一种天然存在的类金属物质，在营养上需要少量，但只有在推荐剂量的两倍时才会变得有毒。英国土壤通常缺乏Se，需要补充，但在火山区和覆盖在磷酸盐或富含有机物质的页岩上的土壤中，Se可能存在过量，这对健康构成了重大挑战。硒在光伏、玻璃生产、化肥和电池中至关重要；预计到2050年，硒需求将增长5-10倍。火山控制着环境中硒(及其化学“孪生”硫磺)的自然来源。由于其极端的挥发性，Se在火山气体、气溶胶和热液流体中富含，从这些流体中Se被沉积在斑岩中，并作为副产品与铜一起开采。到目前为止，由于采集火山气中的Se并在火山岩中对其进行精确分析所涉及的技术挑战，我们对火山Se的定量了解极其有限。我们建议启动一系列新的硒地球化学研究(以及其他对环境重要的痕量挥发性金属的研究)，利用最近利用空载飞行器对高温气体进行采样的发展；以及新的、精确的硒测量分析方案。我们手头已经有了一系列合适的样本，这些样本来自调查人员在最近一系列环境(热点：Cumre Vieja，La Palma，2021年；美国Kilauea，2018年，冰岛Fagradalsfjall；俯冲带：Ambrym火山，瓦努阿图，2018年；以及维拉里卡，2018年)的玄武岩爆炸性喷发期间收集的各种熔岩和气体/气溶胶样本。我们将量化每一次喷发释放出的Se的流量，以及硫磺，以及对其的控制；并确定Se通过喷发以何种化学、生物可利用的形式输送到地表环境。这些目标的成功实现为开展更大规模、综合性和高影响力的研究奠定了基础，这些研究侧重于火山活动向地表环境输送的重金属(例如汞、铊、铅以及硒)、它们的环境去向、生物吸收，包括植物吸收Se和S以及并入地下水所产生的竞争影响，无论是在现代还是在我们星球的历史上。这项研究为改进硒在斑岩矿床中的热液分配模型和可持续、高效的硒资源利用奠定了基础。这个项目探索了一个范围广泛的主题的前沿，通过健康、环境和经济的联系，对整个NERC职权范围产生了影响。

项目成果

Focused Mid-Crustal Magma Intrusion During Continental Break-Up in Ethiopia

埃塞俄比亚大陆破裂期间集中地壳中岩浆侵入

• DOI: 10.1029/2023gl103257
• 发表时间: 2023
• 期刊: Geophysical Research Letters
• 影响因子: 5.2
• 作者: Wong K

Monogenetic volcanoes as windows into transcrustal mush: A case study of Slamet and Loyang volcanoes, Central Java

单生火山是了解穿地壳糊状物质的窗口：以中爪哇省斯拉梅特火山和洛阳火山为例

• DOI: 10.1016/j.jvolgeores.2023.107945
• 发表时间: 2023
• 期刊: Journal of Volcanology and Geothermal Research
• 影响因子: 2.9
• 作者: Barber N