The occurrence of post-subduction magmatism in continental collision zones is a ubiquitous feature of plate tectonics, but its relation with geodynamic processes remains enigmatic. The nature of mantle sources in these settings, and their interaction with subduction-related components, are difficult to constrain using bulk rocks when magmas are subject to mixing and assimilation within the crust. Here we examine post-collisional magma sources in space and time through the chemistry of olivine-hosted melt inclusions and early-formed minerals (spinel, olivine and clinopyroxene) in primitive volcanic rocks from the Neogene–Quaternary East Carpathian volcanic range in Călimani (calc-alkaline; 10.1–6.7 Ma), Southern Harghita (calc-alkaline to shoshonitic; 5.3–0.03 Ma) and the Perșani Mountains (alkali basaltic; 1.2–0.6 Ma). Călimani calc-alkaline parental magma compositions indicate a lithospheric mantle source metasomatised by ~ 2% sediment-derived melts, and are best reproduced by ~ 2–12% melting. Mafic K-alkaline melts in Southern Harghita originate from a melt- and fluid-metasomatised lithospheric mantle source containing amphibole (± phlogopite), by ~ 5% melting. Intraplate Na-alkaline basalts from Racoș (Perșani) reflect small-degree (1–2%) asthenosphere-derived parental melts which experienced minor interaction with metasomatic components in the lithosphere. An important feature of the East Carpathian post-collisional volcanism is that the lithospheric source regions are located in the lower plate (distal Europe-Moesia), rather than the overriding plate (Tisza-Dacia). The volcanism appears to have been caused by (1) asthenospheric uprise following slab sinking and possibly south-eastward propagating delamination and breakoff, which induced melting of the subduction-modified lithospheric mantle (Călimani to Southern Harghita); and (2) decompression melting as a consequence of minor asthenospheric upwelling (Perșani).

中文翻译：

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东喀尔巴阡山脉碰撞后火山作用的不同源区软流圈引起的融化

大陆碰撞带俯冲后岩浆活动的发生是板块构造普遍存在的特征，但其与地球动力学过程的关系仍然是个谜。当岩浆在地壳内受到混合和同化时，这些环境中地幔源的性质以及它们与俯冲相关成分的相互作用很难使用大块岩石进行约束。在这里，我们通过来自 Călimani 的新近纪-第四纪东喀尔巴阡火山范围的原始火山岩中橄榄石熔体包裹体和早期形成矿物（尖晶石、橄榄石和斜辉石）的化学性质，在空间和时间上检查碰撞后的岩浆来源（计算-碱性；10.1–6.7 Ma）、Southern Harghita（钙碱性到钾长石；5.3–0.03 Ma）和 Perșani 山脉（碱性玄武岩；1.2–0.6 Ma）。Călimani 钙碱性母岩浆成分表明岩石圈地幔源由约 2% 的沉积物衍生熔体交代，最好通过约 2-12% 的熔体再现。哈尔吉塔南部的镁铁质钾碱熔体源自熔体和流体交代的岩石圈地幔源，其中含有角闪石（± 金云母），熔化率约为 5%。来自 Racoș (Perșani) 的板内钠碱性玄武岩反映了小程度 (1–2%) 软流圈衍生的母体熔体，这些熔体与岩石圈中的交代组分发生了轻微的相互作用。东喀尔巴阡山脉碰撞后火山作用的一个重要特征是岩石圈源区位于下板块（远欧-摩西亚），而不是上覆板块（蒂萨-达契亚）。火山活动似乎是由 (1) 板块下沉后软流圈上升和可能向东南传播的分层和断裂引起的，这导致了俯冲改造的岩石圈地幔（Călimani 到南哈尔吉塔）的熔化；(2) 减压融化是由于轻微软流圈上升流 (Perșani) 的结果。