Abstract. Back-arc extension superimposed on mountain belts leads to distributed normal faults and shear zones, interacting with magma emplacement in the crust. The composition of granitic magmas emplaced at this stage often involves a component of crustal melting. The Miocene Aegean granitoids were emplaced in metamorphic core complexes (MCC) below crustal-scale low-angle extensional shear zones and normal faults. Intrusion in such contexts interacts with extension and shear along detachments, from the hot magmatic flow within the pluton root zone to the colder ductile and brittle deformation along the detachment. A comparison of the Aegean plutons with the Elba Island MCC in the back-arc region of the Apennines subduction shows that these processes are characteristic of pluton-detachment interactions in general and we discuss a conceptual emplacement scenario, tested by numerical models. Mafic injections within the partially molten lower crust above the hot asthenosphere trigger the ascent within the core of the MCC of felsic magmas, controlled by the strain localization on persistent crustal scale shear zones at the top that guide the ascent until the brittle ductile transition is reached during exhumation. Once the system definitely enters the brittle regime, the detachment and the upper crust are intruded while new detachments migrate upward and in the direction of shearing. Numerical models reproduce the geometry and the kinematic evolution deduced from field observations.

中文翻译：

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Plutons和支队的相互作用，爱琴海和第勒尼安花岗岩的比较

摘要。叠加在山地带上的弧后伸展导致分布正常的断层和剪切带，与地壳中的岩浆作用相互作用。在此阶段放置的花岗岩岩浆成分通常涉及地壳融化的一部分。中新世爱琴海花岗岩位于地壳尺度低角度伸展剪切带和正断层之下的变质岩心复合体中。在这种情况下，侵入与沿分离的伸展和剪切相互作用，从岩体根部区域内的热岩浆流到沿分离的较冷的韧性和脆性变形。在亚平宁山脉俯冲后弧区域的爱琴海海藻与厄尔巴岛MCC的比较表明，这些过程总体上是海藻-水体-水体相互作用的特征，我们讨论了一个概念上的定位方案，并通过数值模型进行了测试。在热流软流圈上方部分熔融的下部地壳内的镁铁质注入触发了长英质岩浆MCC核心内的上升，这受顶部持续性壳尺度剪切带上的应变局部化的控制，从而引导上升，直到达到脆性的韧性转变在掘尸期间。一旦系统确定地进入脆性状态，则侵入和上地壳就会侵入，而新的分离会向上并沿剪切方向迁移。