Comprehensive Study of the Platinum-Group Elements (PGE), and S, Se, and Te in Normal and Hotspot Affected Mid-Ocean Ridge Basalts

正常和热点影响的大洋中脊玄武岩中铂族元素 (PGE) 以及 S、Se 和 Te 的综合研究

• 批准号: 0326658
• 负责人: Jean - guy Schilling
• 金额: $ 37.23万
• 依托单位: University of Rhode Island
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-08-01 至 2007-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0326658&HistoricalAwards=false
• 关键词: Comprehensive; Study; Platinum; Group; Elements

The PIs propose to complete the documentation and study of PGE (Os, Ir, Ru, Pt and Pd) and geochemically related Re, S, Se, Te, as well as Ag and Cd in mid-ocean ridge basalt (MORB) glasses from the URI dredged rock collection. The emphasis will be on their systematic spatial variations relative to interactive mantle plumes and relative fractionation patterns. So far, PGE contents in MORB reported in the literature have been very limited due to a variety of problems. However, the recent use of isotope dilution analyses with high resolution, high sensitivity, inductively coupled plasma-mass spectrometry (HR-ICP-MS) combined with the use of the high pressure asher for sample digestion and equilibration with enriched PGE isotope spikes have now overcome most of these problems. The PIs have developed a HR-ICP-MS isotope dilution method for analyzing these elements, which they now propose to extend to include Os as well. They have also implemented a reliable Hydride Generation, HR-ICP- MS isotope dilution method for analyzing Se and Te, for the purpose of studying the fractionation of S, Se and Te on the same glasses. It is well known that sulphides are important hosts of the PGE and may play key roles in controlling the distribution of PGE and their relative fractionation in the Earth.

项目研究员提议完成对来自URI疏浚岩石收集的大洋中脊玄武岩玻璃中铂族元素（Os、Ir、Ru、Pt和Pd）和与地球化学有关的Re、S、Se、Te以及Ag和Cd的记录和研究。重点将放在它们相对于相互作用的地幔柱和相对分馏模式的系统空间变化上。由于各种问题，迄今为止，文献报道的MORB中PGE含量非常有限。然而，最近使用的同位素稀释分析与高分辨率，高灵敏度，电感耦合等离子体质谱法（HR-ICP-MS）结合使用的高压灰化器的样品消化和平衡与富集的PGE同位素尖峰现在克服了大多数这些问题。PI已经开发了一种HR-ICP-MS同位素稀释法来分析这些元素，他们现在建议将其扩展到包括Os。他们还实施了一种可靠的氢化物发生，HR-ICP- MS同位素稀释法用于分析Se和Te，以研究S，Se和Te在同一玻璃上的分馏。众所周知，硫化物是铂族元素的重要载体，对铂族元素在地球上的分布和相对分馏起着关键作用。