The occurrence of pre-collisional structural and metamorphic fabrics may control the development of new structures during subsequent orogenic deformation. Structural, petrological and geochronological analyses have been performed on selected samples collected along a NW-SE cross section of the Kalak Nappe Complex (KNC) exposed on Kvaloya Island (Finnmark, Norway), in order to define pre-Caledonian or Caledonian affinity of deformation fabrics. Nappes within the KNC experienced different pre-collisional tectonometamorphic histories, resulting in contrasting pre-Caledonian fabrics, which in turn controlled orogen-scale strain partitioning and metamorphic re-equilibration during Caledonian shortening. Caledonian deformation during top-to-SE-directed thrusting occurred at 550–675 °C and 0.8–1.0 GPa in the presence of fluid. Suitably-oriented pre-collisional fabrics were firstly exploited as zones of localized shearing internal to the Nappe and subjected to metamorphic re-equilibration during shortening. Fold geometry during Caledonian thrusting was also controlled by the orientation of pre-Caledonian fabrics. SE-verging asymmetric folds were developed after minor tilting of pre-Caledonian upright folds with orogen-parallel hinge in the hinterland consistently with top-to-SE shearing. Shear-parallel folds displaying orogen-perpendicular hinge lines resulted from top-to-SE general shearing of pre-collisional upright folds showing pre-collisional orogen-perpendicular hinge lines. Caledonian metamorphism appears to have been accompanied by infiltration of radiogenic 40Ar-rich fluids, which affected the Ar isotopic system in synkinematic micas.

中文翻译：

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结构和变质遗传控制造山缩短期间的应变分配（Kalak Nappe Complex，Norwegian Caledonides）

碰撞前构造和变质构造的出现可能控制随后造山变形过程中新构造的发展。对沿暴露在 Kvaloya 岛（芬马克，挪威）的 Kalak Nappe Complex (KNC) 的 NW-SE 横截面收集的选定样本进行了结构、岩石学和地质年代学分析，以定义前加里东期或加里东期变形的亲和力面料。KNC 内的绒毛经历了不同的碰撞前构造变质历史，导致形成对比的前加里东期织物，这反过来又控制了加里东期缩短期间的造山带尺度应变分配和变质再平衡。在有流体存在的情况下，在 550-675°C 和 0.8-1.0 GPa 的温度下，从顶部到东南方向的推力过程中发生加里东变形。适当定向的预碰撞织物首先被用作绒毛内部的局部剪切区，并在起酥油过程中进行变质再平衡。Caledonian 推进过程中的折叠几何形状也受前 Caledonian 织物的方向控制。在腹地具有造山带平行铰链的前加里东期直立褶皱轻微倾斜后，SE 趋向不对称褶皱是在顶部到 SE 剪切一致的情况下形成的。显示造山带垂直铰链线的剪切平行褶皱是由显示前碰撞造山带垂直铰链线的碰撞前直立褶皱从顶部到东南的一般剪切引起的。Caledonian 变质作用似乎伴随着富含放射成因的 40Ar 流体的渗透，这影响了同运动云母中的 Ar 同位素系统。