Constraining the near-surface response to lithospheric reorientation: Structural thermochronology along AlpArray geophysical transects

该提案概述了一个项目，通过创新的组合分析建模方法，量化中阿尔卑斯和东阿尔卑斯挖掘对岩石圈过程（如板块断裂或俯冲极性转换）的假设变化的近地表响应。该项目遵循SPP 4D- mb的目标，通过结合热年代法、平衡截面测量和热运动学建模来重建阿尔卑斯山的4D演化。这种多学科方法将在千米/百万年尺度上解析阿尔卑斯山脉约30 Ma的运动历史，以预测造山带范围内的缩短速率和原始构造的平均滑动速度（RT1-Reorg）。SPP岩石圈（4D-MB）；对关注现今地表运动和地震活动性的互补研究（rt -4- SPP 4D-MB的运动模式和地震活动性）具有重要意义。最重要的是，我们的项目充分考虑了运动历史和大的空间尺度，有助于从深部地壳过程的影响中区分近地表挖掘率（SPP 4D-MB的RT2-Surface Response）。我们建议使用磷灰石和锆石(U-Th)/He和磷灰石裂变径迹法对中阿尔卑斯和东阿尔卑斯（NFP-20E， TRANSALP， EASI）的地质-地球物理样带上采集的60个新样品进行测年。该采样策略(1)覆盖了假定发生俯冲极性转换的区域，(2)与SPP 4 - mb的AF-A （DSEBRA）、AF-C （SWAATH C）和AF-D （SWAATH D）活动场重叠，确保我们的项目与AlpArray的精细地球物理和地球动力学测量相辅相成。我们将通过耦合PECUBE-2DMove热运动学建模方法来反演冷却年龄，保持沿横断面可用和新建平衡截面的预测结构背景。从2Dmove中提取的速度场随后将被纳入热运动学模型（PECUBE），并进行反演，以约束最可能的结构位移和深层岩石圈引起的长波岩石隆升的组合，这些组合可以从复合热年表数据中识别出来。因此，我们提出的项目将大大有助于更好地了解阿尔卑斯山的4D演变。

This proposal outlines a project to quantify the near-surface response of Central and Eastern Alps exhumation to hypothesized changes in lithosphere processes, such as a slab breakoff or a switch in subduction polarity, with an innovative combined analytical-modelling approach. This project follows the aims of the SPP 4D-MB by reconstructing the 4D evolution of the Alps with a combination of thermochronological dating, measurement of balanced cross sections and thermal-kinematic modelling. This multidisciplinary approach will resolve a ~30 Ma kinematic history of the Alps since at kilometre/million year scales to predict orogen-wide shortening rates and average slip velocities of primary tectonic structures (RT1-Reorg. of Lithosphere of the SPP 4D-MB); important context for complimentary studies focusing on the present-day surface motion and seismicity (RT-4-Motion patterns and Seismicity of the SPP 4D-MB). Most importantly, the full consideration of the kinematic history and large spatial scale of our project facilitates the discrimination of near-surface exhumation rates from the influence of deep crustal processes (RT2-Surface Response of the SPP 4D-MB). We propose to date 60 new samples collected along geologic-geophysical transects through the Central and Eastern Alps (NFP-20E, TRANSALP, EASI) with apatite and zircon (U-Th)/He and apatite fission track methods. This sampling strategy (i) covers the area in which a switch in subduction polarity is hypothesized to have occurred and (ii) overlaps with activity fields AF-A (DSEBRA), AF-C (SWAATH C) and AF-D (SWAATH D) of the SPP 4D-MB, ensuring that our project compliments the refined geophysical and geodynamic measurements from AlpArray. We will invert cooling ages with a coupled PECUBE-2DMove thermal-kinematic modelling approach maintaining the predicted structural context of available and newly constructed balanced cross sections along transects lines. Velocity fields extracted from 2Dmove will be subsequently incorporated into a thermal-kinematic model (PECUBE) and inverted to constrain the most likely combination of structural displacements and deep lithosphere induced long-wavelength rock uplift discernable from the composite thermochronological dataset. Our proposed project will therefore significantly contribute to get a better understanding of the 4D evolution of the Alps.