This study presents an investigation of the distribution of trace elements within base metal sulfides from magmatic Ni-Cu-Co deposits from the Proterozoic anorthositic Espedalen Complex, Norway. The mineralisation occurs both as primary, undeformed sulfides and as deformed sulfides hosted within shear zones. Distinct deposits yield Ni tenors ranging from 3 to 10%, allowing the assessment of whether the metal tenor of a deposit is reflected in its sulfide composition. The results allow constraining geological processes spanning from the compositional traits of the parental melts to late-magmatic fluid interactions. Notably, the sulfides exhibit a relatively low concentration of chalcophile elements compared to other Ni-Cu-Co deposits worldwide, particularly platinum-group elements (PGE). This is because these deposits formed from PGE-depleted magmas. Elements compatible with monosulfide solid solution (MSS; Co, Rh, Ru, Ir, Os and Se) are predominantly hosted by sulfides, whereas a smaller proportion of incompatible elements (Pb, Cd, Ag, Bi, Zn, In, Tl, As, Sn and Mo) is also accommodated by sulfides. Our findings for sulfide composition support for the first time a positive correlation between Se concentrations in pentlandite and whole-rock Ni tenors for both Espedalen and magmatic Ni-Cu-Co sulfide deposits worldwide. This is because of the more efficient collection of both Ni and Se by an immiscible sulfide liquid under high R-factor regimes, combined with the fact that Se concentrations in pentlandite remain largely undisturbed during post-cumulus processes as opposed to other trace elements. Consequently, Se concentrations in pentlandite may serve as a proxy for metal enrichment in magmatic sulfide deposits.

本研究对挪威元古界斜长岩埃斯佩达伦杂岩岩浆镍铜钴矿床中的贱金属硫化物中微量元素的分布进行了调查。矿化既以原生的未变形硫化物的形式出现，也以剪切带内的变形硫化物的形式出现。不同矿床的镍品位范围为 3% 至 10%，从而可以评估矿床的金属品位是否反映在其硫化物成分中。这些结果可以限制从母体熔体的成分特征到晚期岩浆流体相互作用的地质过程。值得注意的是，与全球其他镍铜钴矿床相比，硫化物的亲铜元素浓度相对较低，特别是铂族元素 (PGE)。这是因为这些沉积物是由贫铂族元素岩浆形成的。与单硫化物固溶体相容的元素（MSS；Co、Rh、Ru、Ir、Os 和 Se）主要由硫化物组成，而少量不相容元素（Pb、Cd、Ag、Bi、Zn、In、Tl、As ，Sn和Mo）也被硫化物容纳。我们对硫化物成分的研究结果首次支持了全世界 Espedalen 和岩浆 Ni-Cu-Co 硫化物矿床中镍黄铁矿中 Se 浓度与全岩 Ni 品位之间的正相关性。这是因为在高 R 因子条件下，不混溶的硫化物液体可以更有效地收集 Ni 和 Se，而且与其他微量元素相比，镍黄铁矿中的 Se 浓度在积云后过程中基本上不受干扰。因此，镍黄铁矿中的 Se 浓度可以作为岩浆硫化物矿床中金属富集的指标。