Yin Runsheng, Feng Xinbin, Hurley James P, Krabbenhoft David P, Lepak Ryan F, Hu Ruizhong, Zhang Qian, Li Zhonggen, Bi Xianwu
State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China.
Environmental Chemistry and Technology Program, University of Wisconsin-Madison, Madison, WI, 53706, USA.
Sci Rep. 2016 Jan 5;6:18686. doi: 10.1038/srep18686.
During the past few years, evidence of mass independent fractionation (MIF) for mercury (Hg) isotopes have been reported in the Earth's surface reservoirs, mainly assumed to be formed during photochemical processes. However, the magnitude of Hg-MIF in interior pools of the crust is largely unknown. Here, we reported significant variation in Hg-MIF signature (Δ(199)Hg: -0.24 ~ + 0.18‰) in sphalerites collected from 102 zinc (Zn) deposits in China, indicating that Hg-MIF can be recorded into the Earth's crust during geological recycling of crustal material. Changing magnitudes of Hg-MIF signals were observed in Zn deposits with different formations, evidence that Hg isotopes (especially Hg-MIF) can be a useful tracer to identify sources (syngenetic and epigenetic) of Hg in mineral deposits. The average isotopic composition in studied sphalerites (δ(202)Hg average: -0.58‰; Δ(199)Hg average: +0.03‰) may be used to fingerprint Zn smelting activities, one of the largest global Hg emission sources.
在过去几年中，地球表面储库中已报道了汞（Hg）同位素的大规模独立分馏（MIF）证据，主要认为是在光化学过程中形成的。然而，地壳内部储库中汞的MIF程度在很大程度上尚不清楚。在此，我们报道了从中国102个锌（Zn）矿床采集的闪锌矿中汞的MIF特征（Δ(199)Hg：-0.24‰至+0.18‰）存在显著变化，这表明在地壳物质的地质循环过程中汞的MIF能够被记录在地壳中。在不同成因的锌矿床中观察到汞的MIF信号强度变化，这证明汞同位素（尤其是汞的MIF）可以作为识别矿床中汞来源（同生和后生）的有效示踪剂。所研究闪锌矿的平均同位素组成（δ(202)Hg平均：-0.58‰；Δ(199)Hg平均：+0.03‰）可用于追踪锌冶炼活动，锌冶炼是全球最大的汞排放源之一。
