摘要
非传统稳定同位素(Fe-Cu-Zn-Mo)理论与数据相结合提高了科研工作者对地质体系氧化还原过程的理解.本文对这一相对较新的领域进行了综述,包括与氧化还原过程相关的同位素分馏理论和实验约束、时空尺度下的氧逸度以及同位素示踪氧化还原过程.稳定同位素理论预测,Fe-Cu-Zn-Mo同位素应该对氧化还原状态的变化能够做出响应.结果表明,Fe同位素作为岩浆过程、表生过程、俯冲带流体性质"氧逸度计"应用前景广阔;Cu同位素在岩浆、热液、陆地系统可以很好地示踪氧化还原过程;Zn同位素由于络合过程分馏已经被用在许多不同环境中作为含硫/碳流体迁移的敏感示踪剂;Mo同位素作为古氧逸度计可有效重建古海洋-大气氧化还原状态.
Abstract
The combination of non-traditional stable isotope(Fe-Cu-Zn-Mo)theory and data has enhanced the understanding of redox processes in geological systems.This paper provides a comprehensive review of this relative-ly new field,including theoretical and experimental constraints on isotope fractionation behavior related to redox processes,oxygen fugacity at different spatial and temporal scales,and the use of isotopic tracers to study redox processes.Stable isotope theory predicts that Fe-Cu-Zn-Mo isotopes should respond to changes in redox states.The results indicate that Fe isotopes have promising applications as"oxybarometer"for magmatic processes,surface processes,and fluid properties in subduction zones.Cu isotopes can effectively trace redox processes in magmatic,hydrothermal,and terrestrial systems.Zn isotopes,due to their fractionation during complex chelation processes,have been used as sensitive tracers for the migration of sulfur/carbon-bearing fluids in various environments.Mo isotopes serve as paleo-oxybarometer and can be used to reconstruct the ancient ocean-atmosphere redox state effec-tively.
维普
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