The bedrock of Hymittos, Attic peninsula, Greece, exposes a pair of low‐angle crustal‐scale ductile‐then‐brittle detachment faults. The uppermost detachment fault separates sub‐greenschist facies phyllite and marble of a Pelagonian Zone hanging wall, from greenschist facies metasedimentary schist, calc‐schist, and marble correlated to the Cycladic Blueschist Unit. A second, structurally lower detachment fault subdivides the metamorphic rocks of the Cycladic blueschist unit footwall into middle and lower units. There is a marked step in metamorphic grade between the sub‐greenschist facies uppermost package, and the middle‐to‐upper greenschist facies middle and lower packages. A suite of new white mica ⁴⁰Ar/³⁹Ar and zircon (U‐Th)/He dates indicates accommodation of deformation along these faults occurred from the late Oligocene to the late Miocene with both faults active during the middle Miocene. The structures have clear top‐S/SSW kinematics determined from flanking folds, sigmoids, shear bands, stair‐stepping of strain shadows on porphyroclasts, and SCC' fabrics. The ductile‐to‐brittle deformation of the structures, morphology of the massif, and the increase in metamorphic grade suggest these low‐angle structures are part of a major, crustal‐scale extensional complex, located at the northwest end of the West Cycladic Detachment System, that accommodated Miocene bivergent exhumation of Attic‐Cycladic metamorphic core complexes in the central Aegean. Taken together, the above data suggest that multiple coeval detachment branches may form in areas with high strain gradients to accommodate the mechanically necessary termination of Cycladic‐style detachment systems.

中文翻译：

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基克拉迪式分离系统的侧向终止（希腊希米托斯）

希腊阁楼半岛海米托斯（Hymittos）的基岩暴露出一对低角度地壳尺度的韧性-脆性-脆性断裂。最上层的断裂断层将Pelagonian带悬挂壁的亚绿片岩相的花岗石和大理石与与基克拉迪岩片岩单元相关的绿沉积岩片岩，沉积片岩，钙片岩和大理石分开。在结构上较低的第二个断层断层将基克拉迪蓝片岩单元底盘的变质岩细分为中下部单元。在次绿岩相最上层包裹与中上绿岩相中下包裹之间有明显的变质作用。一套新的白云母⁴⁰ Ar / ³⁹Ar和锆石（U‐Th）/ He日期表示从新渐新世晚期到中新世晚期沿这些断层发生变形，而在中新世中期均活跃了两个断层。这些结构具有清晰的top-S / SSW运动学，这些运动学由侧面褶皱，S形，剪切带，卟啉弹性体上的应变阴影和SCC'织物决定。结构的韧性到脆性变形，地块的形态以及变质等级的增加表明，这些低角度的结构是位于西基克拉迪分离队西北端的主要地壳尺度伸展复合体的一部分。该系统容纳了爱琴海中部Attic-Cycladic变质核心复合体的中新世双发掘出土。在一起