Most tonalite–trondhjemite–granodiorite (TTG) suites are Archean–Palaeoproterozoic in age, but those of Neoproterozoic–Phanerozoic age are scarce. A rare Ediacaran high-Al TTG suite has been identified at the Fannani Igneous Complex (FIC) in the northern Arabian–Nubian Shield, which is essentially composed of amalgamated Neoproterozoic island-arc Pan-African composite terranes that contain several ophiolitic sutures. The FIC exhibits a wide range of SiO2, Al2O3, Sr and Zr, shows moderate rare earth element (REE) enrichment, and K, Ti, Nb, Y and heavy REE depletion. It is a subsolvus suite with clear orogenic affinities and strong arc-geochemical signatures. The precise U–Pb zircon thermal ionization mass spectrometry age obtained (607.4 ± 1.95 Ma) indicates oceanic subduction extended to late stages of the East African Orogeny. The FIC exhibits 87Sr/86Sr compositions of 0.70346–0.71091 (Sr(i) ratio, 0.70284), and 143Nd/144Nd of 0.51254–0.51270 (ϵNd(t) = +5.12 to +7.16), typical of modern oceanic-arc rocks (as Japan-arc basalts), and suggestive of mantle sources and island-arc settings. The FIC possesses low values of Yb (1.55 ppm), Nb (14 ppm) and Y (24 ppm), and high ratios of Sr/Y (27), Zr/Sm (46) and Nb/Ta (11.8), typical of magmas produced by anatexis of a basaltic slab. Partial melting models show that the FIC magma was generated by melting (F = 0.25–0.50) of a subducted oceanic crust transformed into eclogite, leaving 10–25% garnet in the residue. The FIC and similar complexes produced via slab melting during the closure of the Mozambique Ocean formed large juvenile belts along the East African Orogen that sutured East and West Gondwana together into a united supercontinent.

中文翻译：

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埃及埃迪卡拉纪英云闪长岩-长长花岗闪长岩-花岗闪长岩组的岩石成因及其对新元古代冈瓦纳组合的影响

英云闪长岩-长长花岗岩-花岗闪长岩（TTG）组多为太古代-古元古代，但新元古代-显生宙的稀少。在阿拉伯-努比亚地盾北部的范纳尼火成岩体 (FIC) 发现了一个罕见的埃迪卡拉纪高铝 TTG 岩体，该岩体主要由合并的新元古代岛弧泛非复合地体组成，其中包含几条蛇绿质缝合线。FIC 表现出广泛的 SiO2, 铝2○3、Sr 和 Zr，显示出适度的稀土元素 (REE) 富集，而 K、Ti、Nb、Y 和重度 REE 贫乏。它是一个亚溶解度套件，具有明显的造山亲和力和强烈的弧地球化学特征。获得的精确 U-Pb 锆石热电离质谱年龄 (607.4 ± 1.95 Ma) 表明海洋俯冲延伸到东非造山运动的晚期。FIC 展品87锶/86Sr 成分为 0.70346–0.71091 (Sr（一世）比率, 0.70284), 和143钕/144Nd 为 0.51254–0.51270 (ϵ钕(吨) = +5.12 至 +7.16)，典型的现代洋弧岩石（如日本弧玄武岩），暗示地幔源和岛弧环境。FIC 具有较低的 Yb (1.55 ppm)、Nb (14 ppm) 和 Y (24 ppm) 值，以及较高的 Sr/Y (27)、Zr/Sm (46) 和 Nb/Ta (11.8) 比值，典型值玄武岩板块深熔产生的岩浆。部分熔融模型表明 FIC 岩浆是由熔融产生的 (F= 0.25–0.50) 的俯冲洋壳转变为榴辉岩，残留物中留下 10–25% 的石榴石。在莫桑比克洋闭合期间，通过板片熔化产生的 FIC 和类似复合体沿着东非造山带形成了大型的幼年带，将东冈瓦纳和西冈瓦纳缝合在一起，形成了一个统一的超大陆。