The first data on the isotopic composition and elemental ratios of nitrogen, carbon, and noble gases in samples from the early stages of the formation of the Guli Complex (Maimecha-Kotui igneous province, Polar Siberia), obtained using the method of stepwise crushing, are reported. The 40Ar/36Ar ratios in the crushing steps vary from the values close to atmospheric (~296) in the meimechite sample to 5000–6000 in pyroxenite and melilitolite; the latter correspond to the estimate for the mantle source of carbonatite from the Guli massif, according to the Ne–Ar systematics. The bulk nitrogen isotopic composition (δ15N) in the studied rocks varies from +3.7 to –5.9‰, showing a regular increase in δ15N with increasing nitrogen concentration; the range of δ15N variations in crushing steps is even wider: from +6.7‰ in pyroxenite to –15.4‰ in meimechite. The data obtained for the ultrabasic rocks of the Guli Massif suggest a significantly lower contribution of the subducted nitrogen of organic origin in comparison with the alkaline–ultramafic rocks of the Kola alkaline province and associated carbonatite, as well as with the Guli carbonatite and some Indian alkaline–ultramafic complexes with carbonatite. The N/36Ar ratios in the trapped mantle component of the ultramafic rocks are 4–8 times lower than that in the associated carbonatite. This, most likely, indicates different fluid sources, or the preferred escape of nitrogen from the fluid phase at the early stages of the formation of the Guli Massif.

中文翻译：

---

古里地块（西伯利亚极地）超镁铁质岩石流体包裹体中 Ar 和 N 的同位素组成和 Ar、N、He 和 C 的元素比

古力杂岩体（迈梅查-科图伊火成岩省，极地西伯利亚）形成早期样品中氮、碳和稀有气体的同位素组成和元素比的首次数据，采用逐步破碎的方法获得，被报道。粉碎步骤中的 40Ar/36Ar 比值从 meimechite 样品中接近大气的值 (~296) 到辉石岩和黄沸石中的 5000–6000；根据 Ne-Ar 系统学，后者对应于古里地块的碳酸岩地幔源的估计。所研究岩石中的整体氮同位素组成 (δ15N) 从 +3.7 到 –5.9‰ 不等，表明随着氮浓度的增加 δ15N 有规律地增加；破碎步骤中 δ15N 的变化范围甚至更广：从辉石岩的 +6.7‰ 到 meimechite 的 –15.4‰。从古力地块超基性岩中获得的数据表明，与科拉碱性省的碱性-超基性岩和伴生碳酸盐岩，以及古力碳酸盐岩和一些印度的碳酸盐岩相比，俯冲的有机成因氮的贡献要低得多。 ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?与碳酸岩的碱性-超镁铁配合物。超基性岩被困地幔组分中的 N/36Ar 比比伴生碳酸盐岩低 4-8 倍。这很可能表明不同的流体来源，或者在古力地块形成的早期阶段，氮从流体相中优选逸出。