Nb/Ta-U/Pb and Th/Pb fractionation in rutile-bearing veins from the Dabie Shan ultrahigh pressure metamorphic belt

大别山超高压变质带金红石矿脉中 Nb/Ta-U/Pb 和 Th/Pb 分馏

• 批准号: 194702212
• 负责人: Professor Dr. Gerhard Wörner
• 金额: --
• 依托单位: School of Earth and Space Sciences
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2011
• 资助国家: 德国
• 起止时间: 2010-12-31 至 2014-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/194702212?language=en
• 关键词: Nb; Ta; Pb; Th; fractionation

We intend to study veins that formed in eclogitic host rocks under high pressure in the famous Dabie Shan-Sulu metamorphic belt. In particular, we will attempt to model and balance trace element budgets in eclogite host and vein assemblage to derive (a) changing fluid compositions, and (b) the composition of the residual eclogite left after dehydration. We will place particular emphasis on the HFSE mass balance and elemental fractionation of, e.g. Nb/Ta, Sm/Nd, Rb/Sr, U/Pb, and Th/Pb. These ratios are critical in evaluating the Nb/Ta variation during subduction processes as well as possible effects of high-pressure fluids on isotopic systems in Earth's reservoirs.

本文对大别山-苏鲁变质带榴辉岩中高压脉体进行了研究。特别是，我们将试图模拟和平衡微量元素收支榴辉岩主机和静脉组合，以获得（a）不断变化的流体成分，和（B）脱水后留下的残余榴辉岩的组成。我们将特别强调HFSE质量平衡和元素分馏，如Nb/Ta，Sm/Nd，Rb/Sr，U/Pb和Th/Pb。这些比值在评估俯冲过程中Nb/Ta的变化以及高压流体对地球储层中同位素系统的可能影响方面至关重要。