Petrogenetic models for the genesis of Archean sanukitoids are diverse in the literature but most point to the initiation of plate tectonics and the construction of the first proto-continents during the Late Archean. These rocks include diorites, monzonites, monzodiorites, quartz monzodiorites, trachyandesites, granodiorites and tonalites, and are defined as having SiO2 = 55–60 wt%, Na2O + K2O = 6 wt%, MgO > 6 wt%, Mg# > 60, Ni–Cr > 100 ppm, Sr and Ba = 600–1800 ppm, chondrite-normalized Ce and Yb values of 80–250 and 4–10, respectively, and no Eu anomalies. Petrogenetic models include the partial melting of mantle peridotite previously metasomatized by fluids of crustal or mantle origin, partial melting of subducted slabs and assimilation of peridotite, and partial melting of undepleted peridotite with subsequent mixing with tonalite–trondhjemite–granodiorite (TTG) crustal partial melts and addition of carbonatite, all of which may or may not include subsequent differentiation by fractional crystallization. Here, extraordinary textural relations unequivocally show that at the Late Archean Otto stock, Abitibi, Canada, sanukitoids resulted from the assimilation of clinopyroxenite by monzonitic magmas and coeval magmatic–hydrothermal Na–K metasomatism. The metasomatized monzonites (± quartz), melanogranites, granodiorites, and sanukitoidal melanoporphyries were subsequently cut by swarms of lamprophyre dykes hosting a different set of hydrothermal alteration assemblages, including propylitic alteration, biotitization, chloritization, and pyritization, along with associated enrichments in Au. These alterations are shown to be associated with the nearby Cadillac–Larder Lake Fault Zone and the world-class Kirkland Lake gold deposit. The Li isotopic compositions of these rocks correlate with Au concentrations and range from magmatic values of ∼ +4 ‰ up to +10·4 ‰ in Na–K metasomatized and Au-depleted rocks, and from magmatic values of ∼4 ‰ down to 0·6 ‰ in rocks hosting propylitic, chloritic, and biotitic alteration and Au enrichments of up to 2·9 ppm Au.

中文翻译：

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通过岩浆混合和 Na-K 交代作用从奥托存量中演化出太古宙 Sanukitoids：来自岩石学观测和锂同位素地球化学的证据

太古宙sanukitoids成因的岩石成因模型在文献中多种多样，但大多数都指向晚太古代晚期板块构造的开始和第一批原始大陆的构造。这些岩石包括闪长岩、二长岩、二长闪长岩、石英二长闪长岩、粗安岩、花岗闪长岩和云闪长岩，定义为SiO2 = 55-60 wt%，Na2O + K2O = 6 wt%，MgO > 6 wt%, Mg# > 60, Ni-Cr > 100 ppm，Sr 和 Ba = 600–1800 ppm，球粒陨石归一化 Ce 和 Yb 值分别为 80–250 和 4–10，没有 Eu 异常。岩石成因模型包括先前被地壳或地幔流体交代的地幔橄榄岩的部分熔融、俯冲板片的部分熔融和橄榄岩的同化，未耗尽的橄榄岩部分熔融，随后与英云长岩-长长花岗岩-花岗闪长岩 (TTG) 地壳部分熔融混合并添加碳酸盐岩，所有这些可能包括也可能不包括随后通过分级结晶进行的分化。在这里，非凡的结构关系明确表明，在加拿大阿比蒂比的晚太古代奥托存量中，sanukitoids 是由二长质岩浆和同时代的岩浆-热液 Na-K 交代作用对斜辉石岩的同化产生的。交代二长岩（±石英）、黑花岗岩、花岗闪长岩和 sanukitoidal 黑斑岩随后被成群的灯藻岩脉切割，这些岩脉拥有一组不同的热液蚀变组合，包括青石蚀变、黑云母化、绿泥石化和黄铁矿化，以及相关的金富集。这些变化与附近的凯迪拉克-拉德湖断层带和世界级的柯克兰湖金矿有关。这些岩石的 Li 同位素组成与 Au 浓度相关，在 Na–K 交代和贫金岩石中的岩浆值从 ∼ +4 ‰ 到 +10·4 ‰ ，从 ∼4 ‰ 的岩浆值到 0 ·6 ‰ 存在于青云石、绿泥石和黑云母蚀变的岩石中，Au 富集度高达 2·9 ppm Au。