Abstract In this work we provide a reappraisal of the mid-Cretaceous extensional basins located to the east of the Pyrenean mountain ranges, from the easternmost portion of Iberia to the Brianconnais Domain of the Western Alps fold-and-thrust belt. These features are reviewed and compared with those of the Bay of Biscay-Pyrenean rift, with the aim of defining geometry, kinematics, timing and lateral extent of the eastern termination of the Mesozoic Iberia-Eurasia plate boundary. Timing and direction of extension, as well as the style of structural segmentation in the Bay of Biscay - Pyrenean rift, are similar to those of basins exposed to the east of the Pyrenean mountain ranges. In both areas, the divergent movement between Iberia and Eurasia caused NNE-SSW oriented extension recorded in WNW-ESE elongated Late Jurassic to mid-Cretaceous basins, segmented by NNE-SSW trending transfer zones. In this work we also individuate and introduce the eastern termination of the Iberia-Eurasia plate boundary. This is the Marguareis extensional system of the Brianconnais Domain of the SW Alps. The crustal-scale Marguareis extensional system involves Paleozoic and Mesozoic rocks and includes a tens of km long transfer fault flanking an extensional domino array that accounted for ca. 2 km of extension along 6 km long sections. When post-Cretaceous alpine rotation is removed, the mid-Cretaceous transfer fault and the extension direction of the Marguareis extensional system become oriented parallel to those of the other portions of the plate boundary, indicating its pertinence to the Bay of Biscay-Pyrenean rift system. Reviewed and newly presented data about the mid-Cretaceous tectonics spanning from the easternmost portion of Iberia to the Western Alps indicate that: (i) the Marguareis extensional system and the extensional structures of south France constituted the easternmost portion of the segmented and laterally terminating Bay of Biscay-Pyrenean rift system; (ii) this easternmost portion of the Iberia-Eurasia plate boundary was characterised by a purely divergent Early to mid-Cretaceous movement.

中文翻译：

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比利牛斯山脉以东的伊比利亚-欧亚板块边界

摘要 在这项工作中，我们重新评价了位于比利牛斯山脉以东的中白垩纪伸展盆地，从伊比利亚的最东部分到西阿尔卑斯山褶皱冲断带的布赖恩康奈地区。审查这些特征并将其与比斯开湾-比利牛斯裂谷的特征进行比较，目的是定义中生代伊比利亚-欧亚板块边界东部终止的几何形状、运动学、时间和横向范围。比斯开湾-比利牛斯裂谷的伸展时间和方向以及构造分割方式与出露在比利牛斯山脉以东的盆地相似。在这两个地区，伊比利亚和欧亚大陆之间的分流运动导致了 WNW-ESE 记录的 NNE-SSW 定向伸展，拉长了晚侏罗世至中白垩世盆地，由 NNE-SSW 趋势转移区分割。在这项工作中，我们还单独介绍了伊比利亚-欧亚板块边界的东部终点。这是西南阿尔卑斯山的布赖恩康奈地区的 Marguareis 伸展系统。地壳尺度的 Marguareis 伸展系统包括古生代和中生代岩石，包括一条数十公里长的转移断层，其两侧是一个伸展多米诺阵列，该阵列占约 沿 6 公里长的路段延长 2 公里。去除白垩纪后高山旋转后，白垩纪中期转移断层和 Marguareis 伸展系统的延伸方向与板块边界的其他部分平行，表明其与比斯开湾-比利牛斯裂谷系统的相关性. 从伊比利亚最东端到西阿尔卑斯山的中白垩世构造的回顾和新呈现的数据表明：(i) Marguareis 伸展系统和法国南部的伸展结构构成了分段和横向终止的海湾的最东部分比斯开-比利牛斯裂谷系统；(ii) 伊比利亚-欧亚板块边界的这个最东端的特征是早白垩世到中白垩世纯粹发散的运动。