Metal-sulfide speciation and cluster formation at deep-sea hydrothermal vents

深海热液喷口的金属硫化物形态和簇形成

• 批准号: 0424789
• 负责人: George Luther
• 金额: $ 11.79万
• 依托单位: University of Delaware
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-07-01 至 2006-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0424789&HistoricalAwards=false
• 关键词: Metal; sulfide; speciation; cluster; formation

Abstract (0424789) - LutherThis project for the Ridge 2000 Postdoctoral Fellowship is an investigation of zinc (Zn),iron (Fe), and sulfide speciation at hydrothermal vents and the mechanisms of metal-sulfide cluster formation at these extreme environments. The approach is based on previous observations at hydrothermal vents of the East Pacific Rise that biological community structure is a function of sulfide and Fe speciation. Sulfide speciation is expected to influence the distribution of organisms at other hydrothermal vent locations such as the Lau Basin. High concentrations of Zn have been measured in vent fluid at the East Lau Spreading Center of the Lau Basin. Because Zn binds to sulfide faster than Fe, Zn is expected to play a key role in sulfide speciation at vents in the Lau Basin. In waters surrounding hydrothermal vents, metals such as Fe and Zn can form clusters with sulfide. These soluble clusters are multinuclear complexes that are stable at concentrations of micromolar or lower. They are likely to serve as building blocks for particles and minerals. Because FeS cluster have been measured at East Pacific Rise vents, ZnS clusters are expected to form at Lau Basin vent habitats. ZnS clusters are particularly stable in aquatic environments; however, much remains unknown concerning the mechanisms of ZnS cluster formation, cluster structure and stability at vent locations.The hypothesis to be tested is chemosynthetic organisms do not thrive near diffuse flowvent waters where metal-sulfide clusters dominate sulfide speciation. In order to betterunderstand metal-sulfide speciation and biological communities at vent habitats, this project will focus on the following objectives: (1) comparison of sulfide and metal speciation in vent diffuse flow regions at the two vent locations; (2) correlation between Zn-sulfide speciation and vent community structure at the Lau Basin site, and (3) assessment of physicochemical conditions that determine ZnS cluster structure, stability and reactivity at vent locations. These objectives will be achieved through a combination of field and laboratory studies. Field studies will focus on vents in the area between 9 degrees 49' and 9 degrees 51'N at the East Pacific Rise and vents at the Valu Fa Ridge in the Lau Basin. Sulfide and metal speciation will be measured by previously established in-situ voltammetric methods. To complement field observations, a series of laboratory studies will attempt to elucidate the mechanism of ZnS cluster formation and cluster structure at these vent habitats. Additional studies are proposed to investigate the reactivity of ZnS clusters with other competing metals and with natural organic matter. This research will have broader impacts by fostering interdisciplinary research andCollaborations. The fellowship will provide a unique opportunity to a postdoctoral fellow who is new to ridge crest science but has research experience in metal-sulfide geochemistry. This research will also contribute to fundamental knowledge of metal and sulfide chemistry in other aquatic systems. Outcomes of this research are expected to have implications for trace metal sulfide biogeochemistry in a variety of aquatic environments ranging from marine sediments to municipal wastewater.

摘要（0424789）- LutherThis项目的岭2000年博士后奖学金是锌（Zn），铁（Fe），硫化物形态在热液喷口和金属硫化物簇形成在这些极端环境的机制的调查。该方法是根据以前在东太平洋海隆热液喷口的观察，生物群落结构是硫化物和铁的形态的功能。硫化物的形成预计会影响其他热液喷口地点，如Lau盆地的生物分布。高浓度的锌已被测得在喷口流体在东刘扩展中心的刘盆地。由于锌结合硫化物的速度比铁，锌预计将发挥关键作用的硫化物形态在劳盆地的喷口。 在热液喷口周围的沃茨中，铁和锌等金属可与硫化物形成簇。这些可溶性簇是在微摩尔或更低浓度下稳定的多核络合物。它们很可能是颗粒和矿物质的组成部分。由于在东太平洋海隆喷口测量到FeS簇，预期在Lau盆地喷口生境形成ZnS簇。ZnS集群是特别稳定的水生环境中，然而，很多仍然未知的机制ZnS集群的形成，集群结构和稳定性在ventlocations.The假设进行测试是化能合成生物不兴旺附近的扩散flowvent沃茨，金属硫化物集群占主导地位的硫化物形态。为了更好地了解喷口生境中的金属硫化物形态和生物群落，本项目将着重于以下目标：（1）比较两个喷口扩散流区硫化物和金属形态;（2）Lau盆地的硫化锌形态与喷口群落结构之间的相关性，以及（3）确定ZnS簇结构的物理化学条件的评估，稳定性和反应性。 这些目标将通过实地研究和实验室研究相结合来实现。实地研究将侧重于东太平洋海隆北纬9度49'至9度51'之间地区的喷口和劳盆地瓦卢法海岭的喷口。硫化物和金属形态将通过先前建立的原位伏安法测量。为了补充现场观测，一系列的实验室研究将试图阐明在这些喷口栖息地的ZnS集群的形成和集群结构的机制。提出了进一步的研究，以调查与其他竞争金属和天然有机物的ZnS簇的反应性。 这项研究将通过促进跨学科研究和合作产生更广泛的影响。该奖学金将提供一个独特的机会，博士后研究员谁是新的脊冠科学，但在金属硫化物地球化学的研究经验。这项研究也将有助于其他水生系统中的金属和硫化物化学的基础知识。这项研究的结果预计将有影响的痕量金属硫化物在各种水生环境中，从海洋沉积物到城市污水。