银同位素地球化学综述

A Review of Silver Isotope Geochemistry

银(Ag)是生活中常见的贵金属元素。Ag有2个稳定同位素107Ag和109Ag。随着多接收电感耦合等离子体质谱仪(MC-ICP-MS)的应用,国内外对银同位素体系开展了一系列研究。Ag在矿床中常与Au元素共生,且Pd-Ag同位素体系可作为早期太阳系演化计时器,因此在天体化学、环境科学、矿床地球化学等领域都具有广泛应用。本文首先介绍了银同位素的地球化学特点及其研究历史,对前人工作进行了系统总结,包括化学分离流程、质谱测定及质量分馏校正方法、储库同位素组成,评述了银同位素在地球科学及交叉学科中的应用。最后总结了银同位素地球化学研究的难点,展望了银同位素储库组成和分馏机理研究。

Silver(Ag) is a common noble metal element widely used in daily life. It has two stable isotopes, 107Ag and 109Ag. With the development of multiple-collector inductively coupled plasma mass spectrometry(MC-ICP-MS), research of Ag isotopes has been increasingly carried out. Because Ag often coexists with gold in ore deposits and because the Pd-Ag chronometer is often used in timing the early solar system, Ag isotopes are widely studied in cosmochemistry, environmental science, deposit geochemistry, and other research fields. In this paper, we summarize recent research progresses on analytical methods of Ag isotopes, including chemical separation, mass spectrometry analysis, reservoir determination, and on applications of Ag isotopes in geoscience and interdisciplinary fields. Finally, we emphasize the challenges in Ag isotope studies and propose future studies on determining isotopic compositions of Ag reservoirs and on understanding fractionation mechanisms of Ag isotopes.