Rhenium-Osmium Isotope Systematics of Tektites and Impact Glasses

玻璃陨石和冲击玻璃的铼锇同位素系统学

• 批准号: 9218847
• 负责人: Steven Shirey
• 金额: $ 1.8万
• 依托单位: Carnegie Institution of Washington
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-01-15 至 1994-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9218847&HistoricalAwards=false
• 关键词: Rhenium; Osmium; Isotope; Systematics; Tektites

Tektites are the product of melting and quenching of terrestrial rocks during hypervelocity impacts on the Earth. The advent of the highly-sensitive negative thermal ionization technique (NTIMS) for Re-Os isotopic analysis makes this system ideally suited to the problem of understanding the often elevated siderophile element content of tektites. The P.I.s propose to carry out Re-Os isotopic studies by NTIMS on tektites from the Australasian and Ivory Coast Strewn fields and on the Auoelloul glasses. With the Re-Os isotopic system there is the unique opportunity to determine if the Os found in tektites is really extraterrestrial, crustal or a mixture of both. This is necessary for showing whether the siderophile element signatures in tektites are a result of meteorite contamination or in-situ reduction of the target rocks.

陨石是地球上的岩石在超高速撞击过程中熔化和淬火的产物。用于Re-Os同位素分析的高灵敏度负热电离技术（NTIMS）的出现使该系统非常适合于理解陨石中经常升高的亲铁元素含量的问题。P.I.s提议由NTIMS对来自澳大利亚和象牙海岸散布地区的陨石以及Auoelloul玻璃进行Re-Os同位素研究。有了Re-Os同位素系统，就有了一个独特的机会来确定在陨石中发现的o是否真的是外星的，地壳的还是两者的混合物。这对于证明陨石中的亲铁元素特征是陨石污染的结果还是目标岩石原位还原的结果是必要的。