Transpression and transtension in the Eastern Alps (TATEA): Kinematics and age of a sinistral wrench zone

阿德里亚，非洲的北部支线，与欧洲相撞，形成了欧洲阿尔卑斯山，与东南部的迪纳里德山脉相连，并被帕诺尼亚盆地中断，到达东部的喀尔巴底山脉。在深处，在欧洲阿尔卑斯山的造山分叉之下，大致与三个板块之间的三重交汇处(带)在空间上重合。它们位于欧洲和亚得里亚海板块，外加潘尼期岩石圈碎片。它们的几何形状和排列取决于当前的研究(AlpArray，SPP 2017 MB-4D)。在地表，(晚期)亚得里亚海的凹陷导致了两个(活动的)地震构造扭动带，它们在尼德雷牛头山交汇，呈高角度/垂直于山链。我们将集中于Radstädter、Schladminger、Wölzer和Seckauer Tauern的中上地壳的构造和年代学，这里概括为Niedere Tauern(图2)。我们的目标是建立东阿尔卑斯山新生代扭动带在它们交汇处的运动学模型(图2)。我们将结合构造地质学，揭示新生代剪切和断裂带的演化，以及地质年代学，变形和折返年龄。总而言之，这些都是将表面表达与深层结构联系起来的最有前途的工具。Niedere Tauern的运动学，它与西部的Tauern窗口和东部的Pöls-Lavanttal断层的连接，对于理解从欧洲阿尔卑斯山到喀尔巴西亚和迪纳里德斯的构造分叉是不可或缺的拼图(图1)。造山带中表层与深层结构的联系促进了对造山作用的过程驱动的理解，这种理解适用于其他造山带。我们将通过结构映射来探索Niedere Tauern的运动学，特别是结构收敛。为了量化变形的时间、序列和区域差异，我们将使用40Ar/39Ar原位、裂变径迹和(U-Th)/He方法进行地质年代学研究。期望的结果将是Niedere Tauern检验东阿尔卑斯山的扭扭带和扭扭带是同源、共轭和等时活动的一致的结构和时间模式，或者这些带是否有不同的原因。这一差异对阿尔卑斯山-喀尔巴山-迪纳里德系统的地球动力学重建具有重要意义。

Adria, the northern spur of Africa, collided with Europe and formed the European Alps, which connect to the Dinarides in the Southeast, and intermitted by the Pannonian Basin to the Carpathians in the East. At depths, beneath this orogenic bifurcation of the European Alps, roughly coincide spatially with the triple junction (zone) between three plates. That are in the European and Adriatic plates, plus the Pannonian lithospheric fragment. Their geometry and arrangement are subject to current research (AlpArray, SPP 2017 MB-4D). At the surface, the (late) Adriatic indentation caused two (active) seismotectonic wrench zones of high-angle/perpendicular to the mountain chain that meet in the Niedere Tauern. We will focus on the tectonics and chronology of the middle–upper crust in the Radstädter, Schladminger, Wölzer and Seckauer Tauern, here summarized as the Niedere Tauern (Fig. 2). We aim to establish a kinematic model for the Cenozoic wrench zones of the Eastern Alps in the area where they meet (Fig. 2). We will combine structural geology, unravelling the Cenozoic shear and fault zone evolution, and geochronology, dating deformation and exhumation. Together these are the most promising tools to link surface expressions to the deep structure. The kinematics of the Niedere Tauern, its connection to the Tauern Window in the west and to the Pöls-, Lavanttal faults in the east, is an indispensable jigsaw piece to understand the structural bifurcation from the European Alps to the Carpathians and Dinarides (Fig. 1). The linkage of surface to deep structures in orogens promotes a process-driven understanding of orogeny that is applicable in other orogens. We will explore the kinematics, especially the structural vergence, of the Niedere Tauern by structural mapping. To quantify the timing, sequence, and regional differences in deformation, we will perform geochronology using the 40Ar/39Ar in-situ, the fission-track and the (U-Th)/He methods. The aspired outcome will be a coherent structural and temporal pattern of the exhumation in the Niedere Tauern testing whether the transpressional to transtensional wrench zones in the Eastern Alps are cogenetic, conjugated and isochronously active or whether these zones have different causes. This difference has major implication for the geodynamic reconstruction of the Alpine-Carpathian-Dinaride system.