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

亚德里亚，非洲的北端，与欧洲相撞，形成了欧洲的阿尔卑斯山脉，它与东南部的第纳里德斯山脉相连，被潘诺尼亚盆地与东部的喀尔巴阡山脉隔开。在深处，在欧洲阿尔卑斯山脉的造山分岔之下，在空间上大致与三个板块之间的三重接合（带）重合。它们位于欧洲和亚得里亚海板块，加上潘诺尼亚岩石圈碎片。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）亚得里亚海压陷形成了两个（活跃的）高角度/垂直于山脉链的地震构造扳手带，并在Niedere Tauern交汇。我们将重点研究Radstädter、Schladminger、Wölzer和Seckauer Tauern（这里概括为Niedere Tauern）中上部地壳的构造和年代学（图2）。我们的目标是建立东阿尔卑斯新生代扳手带交汇区域的运动学模型（图2）。我们将结合构造地质学，揭示新生代剪切断裂带演化，结合地质年代学，确定变形和挖掘的年代。这些都是最有希望将地表表达与深层结构联系起来的工具。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，是理解从欧洲阿尔卑斯山到喀尔巴阡山脉和Dinarides的构造分支不可缺少的拼图（图1）。造山带表面与深层构造的联系促进了对造山带过程驱动的理解，这种理解也适用于其他造山带。我们将通过结构映射来探讨Niedere taun的运动学，特别是结构收敛性。为了量化变形的时间、顺序和区域差异，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。期望的结果将是在Niedere Tauern发掘出一个连贯的结构和时间模式，以测试东阿尔卑斯的转扭-张扭带是否是同生的、共轭的和等时活动的，或者这些带是否有不同的原因。这种差异对阿尔卑斯-喀尔巴阡-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.