Sediment-hosted Pb-Zn mineralization occurs in the Mârmorilik and Qaarsukassak formations of the Paleoproterozoic Karrat Group in arctic West Greenland. The timing and model of mineralization of the historical Pb-Zn Black Angel Mine in the Mârmorilik Formation and how it might be related to Pb-Zn mineralization in the nearby Qaarsukassak Formation is enigmatic. This study aims to understand the origin of the Pb-Zn mineralization in both formations by petrographic analysis, pyrite- and ore-sulfide sulfur isotope analysis, Pb-Pb isotope analysis, and Re-Os isotope analysis of pyrite associated with the mineralization. Sulfur isotope results from secondary ion mass spectrometry show a range of δ³⁴S values between 0‰ and +6.9‰ on sulfide minerals (pyrite, sphalerite, galena, pyrrhotite); isotopic fractionations and geothermometry suggest contributions from both bacterial sulfate reduction and abiotic thermochemical sulfate reduction processes. Isotopic analysis (Pb-Pb) of galena from ore zones hosted by the Mârmorilik Formation shows a relatively homogenous Pb isotope signature that is consistent with local basement as a likely source for the metals. Results from Re-Os analysis of pyrite indicate that the Mârmorilik and Qaarsukassak mineralizing events are Paleoproterozoic. Ore textures and mineralogy, as well as S and Pb isotope data, associated with the carbonate-hosted Mârmorilik Formation are most consistent with a Mississippi Valley-type (MVT) deposit model, whereas characteristics of the dominantly siliciclastic-hosted Qaarsukassak mineralization textures are most consistent with a sedimentary exhalative (SEDEX) mineralization model. The Mârmorilik (Black Angel) mineralization represents the oldest documented MVT deposit outside of the Neoarchean–Paleoproterozoic Transvaal basin in South Africa.

沉积物沉积的铅锌矿化发生在北极西格陵兰古元古代Karrat组的Mârmorilik和Qaarsukassak地层中。莫莫里里克组中历史悠久的铅锌黑天使矿山的成矿时间和模型，以及它与附近的卡苏卡萨克组中铅锌矿化的关系如何，目前尚不清楚。本研究旨在通过岩相分析，黄铁矿和矿石硫化物硫同位素分析，Pb-Pb同位素分析以及与矿化有关的黄铁矿的Re-Os同位素分析来了解两种地层中Pb-Zn矿化的起源。从二次离子质谱硫同位素结果光谱显示范围δ的³⁴ 0‰和硫化物矿物（黄铁矿，闪锌矿，方铅矿，黄铁矿）+ 6.9‰之间的价值观; 同位素分级和地热法表明细菌硫酸盐还原和非生物热化学硫酸盐还原过程都有贡献。方铅矿的同位素分析（Pb-Pb）由Mârmorilik组所容纳的矿带显示出相对均一的Pb同位素特征，这与作为金属的可能来源的局部基底一致。黄铁矿的Re-Os分析结果表明，Mármorilik和Qaarsukassak的成矿事件是古元古代的。矿石质地和矿物学碳酸盐岩Mârmorilik组的碳酸盐，S和Pb同位素数据与密西西比河谷型（MVT）矿床模型最一致，而以硅质碎屑岩为主的Qaarsukassak矿化纹理的特征与沉积相最一致呼气（SEDEX）矿化模型。Mârmorilik（黑天使）矿床是南非新archarean-Paleoproterozoic特兰斯瓦尔盆地外最古老的MVT矿床。