Partitioning of Se, As, Sb, Te and Bi between monosulfide solid solution and sulfide melt - Application to magmatic sulfide deposits
Partitioning of Se, As, Sb, Te and Bi between monosulfide solid solution and sulfide melt - Application to magmatic sulfide deposits
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DOI：
10.1016/j.gca.2010.08.009
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发表时间：
2010-11-01
影响因子：
5
通讯作者：
Laurenz, Vera
中科院分区：
文献类型：
--
作者：
Helmy, Hassan M.;Ballhaus, Chris;Laurenz, Vera
硫属元素（S、Se、Te）、半金属（As、Sb）和金属 Bi 是贵金属的重要配体，并与铂族元素 (PGE) 形成各种成分多样的矿物。除了 S 之外，很少有实验数据可以量化这些元素在岩浆硫化物系统中的行为。在这里，我们报告了 Se、Te、As、Sb 和 Bi 在单硫化物固溶体 (mss) 和硫化物熔体之间的实验分配系数，该系数是在 950 摄氏度下、在由 Fe-FeS（金属-硫铁矿）和 Fe1-xS-S-x（mss-硫）平衡所包围的一系列硫逸度 (fS(2)）下测定的。显示硒作为取代 S2- 的阴离子分配在 MS 饱和的硫化物熔体中。砷随 fS(2) 改变其氧化态，从低 fS(2) 时以阴离子形态为主变为高 fS(2) 时以阳离子形态为主。元素 Sb、Te 和 Bi 与 mss 非常不相容，因此它们只能以阳离子和/或中性金属物质的形式存在于硫化物熔体中。导出的分配系数随着元素原子半径的增加而下降。它们还反映了元素周期表中各个元素的位置：在一个族内（例如，As、Sb、Bi），分配系数随着原子半径的增加而下降，并且在一个周期内，第 15 族的元素比第 16 族的相邻元素与 mss 更不相容。 (C) 2010 Elsevier Ltd. 保留所有权利。
The chalcogenes (S, Se, Te), semimetals (As, Sb) and the metal Bi are important ligands for noble metals and form a wide range of compositionally diverse minerals with the platinum-group elements (PGE). With the exception of S, few experimental data exist to quantify the behavior of these elements in magmatic sulfide systems. Here we report experimental partition coefficients for Se, Te, As, Sb, and Bi between monosulfide solid solution (mss) and sulfide melt, determined at 950 degrees C at a range of sulfur fugacities (fS(2)) bracketed by the Fe-FeS (metal-troilite) and the Fe1-xS-S-x (mss-sulfur) equilibria. Selenium is shown to partition in mss-saturated sulfide melt as an anion replacing S2-. Arsenic changes its oxidation state with fS(2) from predominantly anionic speciation at low fS(2), to cationic speciation at high fS(2). The elements Sb, Te, and Bi are so highly incompatible with mss that they can only be present in sulfide melt as cations and/or as neutral metallic species. The partition coefficients derived fall with increasing atomic radius of the element. They also reflect the positions of the respective elements in the Periodic Table: within a group (e.g., As, Sb, Bi) the partition coefficients fall with increasing atomic radius, and within a period the elements of the 15th group are more incompatible with mss than the neighboring elements of the 16th group. (C) 2010 Elsevier Ltd. All rights reserved.