The ca. 3.0 Ga Ni sulfide mineralisation at Maniitsoq, SW Greenland, is hosted by a cluster of relatively small, irregularly shaped mafic-ultramafic intrusions, typically 10s of m to a few km across, that are lodged within broadly coeval gneiss. Many of the intrusions are fault bounded and fragmented so that their original sizes remain unknown. The sulfides form disseminations and sulfide matrix breccia veins displaying sharp contacts to the host intrusives. The mineralisation has relatively high Ni/Cu, with 4–10% Ni and 1–2% Cu. Correlations between Ni and Cu with sulfide content are strong, consistent with a magmatic origin of the mineralisation. PGE contents are mostly below 0.5 ppm, and Cu/Pd is typically above primitive mantle levels, interpreted to reflect equilibration of the parent magma with segregating sulfide melt prior to final magma emplacement. Sulfide segregation was likely triggered by assimilation of crustal sulfur, as suggested by whole rock S/Se ratios of 7000–9000. The sulfide melt underwent extensive fractionation after final emplacement, caused by downward percolation of Cu-rich sulfide melt through incompletely solidified cumulates. We suggest that the exposed Maniitsoq intrusions represent the Ni-rich upper portions of magma conduits implying that there is potential for Cu-rich sulfides in unexposed deeper portions of the belt.

约。格陵兰岛西南部 Maniitsoq 的 3.0 Ga Ni 硫化物矿化体由一组相对较小、形状不规则的镁铁质-超镁铁质侵入体组成，直径通常为 10 米到几公里，位于广泛的同时代片麻岩中。许多侵入体都受断层限制且呈碎片状，因此它们的原始大小仍然未知。硫化物形成播撒物和硫化物基质角砾岩脉，与宿主侵入体表现出尖锐的接触。矿化具有较高的Ni/Cu含量，其中Ni含量为4%~10%，Cu含量为1%~2%。镍和铜与硫化物含量之间的相关性很强，与矿化的岩浆起源一致。 PGE 含量大多低于 0.5 ppm，Cu/Pd 通常高于原始地幔水平，解释为反映了母岩浆在最终岩浆就位之前与分离的硫化物熔体的平衡。硫化物偏析可能是由地壳硫的同化引发的，整个岩石的 S/Se 比率为 7000-9000，表明这一点。最终就位后，硫化物熔体经历了广泛的分馏，这是由于富铜硫化物熔体通过不完全凝固的堆积物向下渗透造成的。我们认为暴露的马尼索克侵入体代表了岩浆通道的富镍上部部分，这意味着在该带未暴露的更深部分中存在富铜硫化物的潜力。