Zinc Isotope Fractionation as an Indicator of Geochemical Attenuation Processes

详细信息    查看全文

• 作者：Harish Veeramani ; Jane Eagling ; Julia H. Jamieson-Hanes ; Lingyi Kong ; Carol J. Ptacek ; David W. Blowes
• 刊名：Environmental Science & Technology Letters
• 出版年：2015
• 出版时间：November 10, 2015
• 年：2015
• 卷：2
• 期：11
• 页码：314-319
• 全文大小：322K

文摘

Isotope ratio measurements have been used to trace environmental processes, especially in subsurface environments. In this study, we evaluated the potential to use zinc (Zn) stable isotope ratios as indicators of attenuation processes, including sorption and precipitation. Zn isotope fractionation was observed during distinctly different precipitation processes. Isotope measurements confirmed an increasing trend in aqueous 未⁶⁶Zn in solution during sphalerite (ZnS) formation, but a decreasing trend in 未⁶⁶Zn during the precipitation of hydrozincite [Zn₅(CO₃)₂(OH)₆] and hopeite [Zn₃(PO₄)₂路4H₂O]. In contrast, time-dependent sorption of Zn onto ferrihydrite at a fixed pH did not cause isotopic fractionation in the solution over the duration of the experiments. These findings suggest potential applications of stable isotope measurements in aqueous environments for determining reaction pathways (e.g., precipitation with common groundwater constituents) leading to Zn attenuation.