Carbon and Oxygen Isotope Studies of Diamonds, Their Inclusions and Mantle Xenoliths

钻石、其包裹体和地幔捕虏体的碳和氧同位素研究

• 批准号: 9017378
• 负责人: Peter Deines
• 金额: $ 11.5万
• 依托单位: Pennsylvania State Univ University Park
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1991
• 资助国家: 美国
• 起止时间: 1991-01-01 至 1994-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9017378&HistoricalAwards=false
• 关键词: Carbon; Oxygen; Isotope; Studies; Diamonds

The published record indicates that a multiplicity of fluids is involved in mantle processes leading to the formation of kimberlites and diamonds. It is the purpose of the proposed work to contribute to the clarification of the emerging very complex picture of diamond growth and mantle metasomatism. In particular the PI will attempt to trace the distribution and origin of highly 13C depleted mantle carbon further, following the leeds developed by the work carried out so far. A major new thrust of the proposed work will be the examination of the oxygen isotope record of silicate in inclusions in diamonds and the carbon isotopic composition of the host. The studies will be carried out on suites of samples for which an asthenospheric origin can be postulated as well as on diamonds which were formed at shallower levels. The results of the work will provide an important constraint for hypotheses proposing subduction related origins of diamonds which were formed at 400 to 500 km depth. It is also planned to delineate further the various mantle carbon reservoirs that are presently under discussion, and to establish the joint 813C and 818O record left by mantle metasomatic events.

已发表的记录表明， 参与了地幔过程， 金伯利岩和钻石 这是拟议工作的目的 帮助澄清正在出现的非常复杂的 金刚石生长和地幔交代作用的图片。 特别是 PI将尝试追踪 继利兹事件之后， 通过迄今为止开展的工作。 拟议工作的一个主要新重点将是审查 包裹体中硅酸盐的氧同位素记录 钻石和宿主的碳同位素组成。 的 将对一组样本进行研究，其中 软流层起源可以假定， 形成于较浅的层面。 的工作成果 将为提出的假设提供重要约束 与俯冲有关的钻石起源于400 到500公里的深度。 还计划进一步划定各种地幔碳 目前正在讨论的水库，并建立 地幔交代事件留下的~（813）C和~（818）O记录。