The He-Ne-Ar-H2O-CO2 isotope and abundance systematics of the Reykjanes Ridge: Constraints on plume-ridge interaction and the degassing history of the Icelandic hotspot

雷克雅内斯海脊的 He-Ne-Ar-H2O-CO2 同位素和丰度系统学：羽流-山脊相互作用的约束和冰岛热点的脱气历史

• 批准号: 0095885
• 负责人: David Hilton
• 金额: $ 13.69万
• 依托单位: University of California-San Diego Scripps Inst of Oceanography
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-11-15 至 2005-10-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0095885&HistoricalAwards=false
• 关键词: He; Ne; Ar; H2O; CO2

This proposal addressees fundamental questions related to the origin of the earth's mantle and atmosphere, the history of mantle flow and present mantle processes, and the nature of mantle melting and the interaction of mantle plumes with ambient mantle. More specifically, the goals of the proposal are to understand the processes of mixing and mantle flow that accompany the interaction of a mantle plume with the normal mantle below mid-ocean ridges. The approach of this proposal is to look at volatile abundances and isotope ratios, especially H, He, Ne, Ar, and CO2 and H2O. Well-characterized dredged samples are available from UK investigators for the Reykjanes Ridge between 57 and 63 degrees north. Preliminary 3He/4He and He abundance data show that degassing is an important process north of 61 degrees, where shoaling eruption depth results in extensive degassing and low He abundances. There are five individual hypotheses that can be tested with the data to be collected, most having to do with the intrinsic processes that happen in combination with apparent 2-component mixing of plume and MORB mantle seen with other components. The noble gas data will be collected by crushing, stepped combustion and with a laser probe, a new and promising method.

这一提议涉及到与地球地幔和大气的起源、地幔流动的历史和现今地幔过程、地幔熔融的性质以及地幔柱与环境地幔的相互作用有关的基本问题。更具体地说，该提案的目标是了解伴随着地幔柱与大洋中脊以下正常地幔相互作用的混合和地幔流动过程。该建议的方法是观察挥发性丰度和同位素比率，特别是H、He、Ne、Ar和CO2和H2O。英国调查人员在北纬57度至63度之间的雷克雅未克海脊发现了特征良好的疏浚样本。初步的3 He/4 He和He丰度数据表明，61度以北是一个重要的脱气过程，浅喷发深度导致广泛的脱气和低He丰度。有五个单独的假设，可以测试与收集的数据，大多数有做的内在过程中发生的组合与明显的2组分混合的羽和MORB地幔与其他组件。惰性气体数据将通过破碎、分级燃烧和激光探针收集，这是一种新的和有前途的方法。