The tectonic framework of the North China Craton (NCC) involved the building of microblocks and their incorporation into larger crustal blocks during the Late Archean followed by final cratonization through collisional assembly of the crustal blocks during the Late Palaeoproterozoic. Here we investigate a newly identified gabbro‐diorite‐anorthosite suite, metamorphosed under granulite facies, along the margin of the Qianhuai microblock based on field, petrological, geochemical and zircon U–Pb and Lu–Hf studies, with a view to understand the petrogenetic and metamorphic history. Mineral phase equilibria modelling of metagabbros from the suite reveals relatively high temperatures and pressures of 800–820°C and 13–14 kbar, with a typical isobaric cooling pressure–temperature path characterized by initial heating followed by moderate to high‐pressure metamorphism and cooling, consistent with a thickened arc setting. The gabbro–diorite–anorthosite association is considered to represent the fractionated sequence from a common mafic magma. Magmatic zircon grains from the metagabbro yield upper intercept ages of 2522 and 2540 Ma, corresponding to the timing of formation of the mafic protolith. The lower intercept ages of 1785 and 1833 Ma mark the timing of metamorphism associated with the collisional event between the Western and Eastern blocks of the NCC. Zircon ε_Hf(t) values are mostly positive for the magmatic domains suggesting that the melts were derived from depleted mantle sources. The Hf model ages indicate that the magma source involved Neoarchean–Mesoarchean juvenile components and the continental crust was reworked during metamorphism in the Late Palaeoproterozoic. The lithological association and geochemical as well as isotopic features are consistent with a convergent margin setting along a continental arc, where basaltic melts were underplated beneath the overriding arc, accompanied by lower crustal melting. Our study confirms subduction‐related crust building events during the late Neoarchean followed by Late Palaeoproterozoic high‐grade metamorphism associated with the final cratonization of the NCC.

中文翻译：

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华北克拉通前淮微区块边缘新生代岩浆作用和古元古代变质作用

华北克拉通（NCC）的构造框架涉及微块的建造，并在太古宙晚期将其并入较大的地壳中，然后通过古元古代晚期地壳块的碰撞组装而最终进行克拉通作用。在这里，我们根据田野，岩石学，地球化学和锆石U-Pb和Lu-Hf研究，研究了一个新发现的辉长岩-闪长岩-钙长石斜体，沿着前淮微区块的边缘在粒岩相下变质，目的是了解成岩作用和变质的历史。该套件中偏斜矿物的矿物相平衡模型揭示了相对较高的温度和压力（800-820°C和13-14 kbar），具有典型的等压冷却压力-温度路径，其特征是先加热，然后进行中等至高压变质和冷却，并与增厚的电弧设置保持一致。辉长岩-闪长岩-钙正石的结合被认为代表了普通镁铁质岩浆的分离序列。来自异辉石的岩浆锆石晶粒产生的上部拦截年龄为2522和2540 Ma，这与镁铁质原生质形成的时间相对应。1785年和1833 Ma的较低拦截年龄标志着与NCC西部和东部区块之间的碰撞事件有关的变质时间。锆石 来自异辉石的岩浆锆石晶粒产生的上部拦截年龄为2522和2540 Ma，这与镁铁质原生质形成的时间相对应。1785年和1833 Ma的较低拦截年龄标志着与NCC西部和东部区块之间的碰撞事件有关的变质时间。锆石 来自异辉石的岩浆锆石晶粒产生的上部拦截年龄为2522和2540 Ma，这与镁铁质原生质形成的时间相对应。1785年和1833 Ma的较低拦截年龄标志着与NCC西部和东部区块之间的碰撞事件有关的变质时间。锆石ε_的Hf（吨）值是用于表明熔化物从亏损地幔来源岩浆域多为阳性。高频模型年龄表明，岩浆源涉及新古宙—中古统的幼体成分，并且在古元古代晚期变质过程中对大陆壳进行了改造。岩石学上的联系，地球化学以及同位素特征与大陆弧上的汇聚边缘相一致，其中玄武质熔体被底层覆覆在上覆弧之下，并伴随着较低的地壳融化。我们的研究证实了与新大陆时代晚期俯冲有关的地壳形成事件，随后是与古克拉通最终克拉通化有关的古元古代晚期高变质。