Dynamische Modellierung der Andenorogenesek eingebettet in ein 3D Kugelschalenmodell des Erdmantels

安第斯造山运动的一些基本特征不能仅仅用一个动态的区域模式来解释，因为在它的垂直边界上有重要的影响。安第斯山脉的动态区域模型应该嵌入三维球壳模型中。由于爬行速度的极向和环向部分的能量分布，以及安第斯山脉沿线的地质决定的物质运输，这两个模型都必须是三维的。在岩石圈-软流圈边界和深度分别为410、520和660 km处建立了新的地幔粘度剖面。因此，代码Terra现在面临的挑战实际上更大了。在过去三年中，我们通过国际合作解决了这些问题（见2.2 b）)。基于新的粘度曲线和改进的Terra，我们计算了一个新的正向球壳模型[103,104]。已经提交了关于Terra改进的论文[56,70]。我们设想了一个具有相同新粘度剖面的安第斯造山作用的区域模型（3.2 b）。我们想研究为什么在安第斯山脉的某些部分有平板俯冲，为什么地壳变形和火山活动向东迁移。不相容元素丰度的演变表明一个循环是通过一个快速的过程完成的，可能是由于下板块的大规模分层，也可能是由于另一种类型的分层。结合另一个球壳模型（有规定的板块边界），区域模型应该在数值上解释为什么高原型造山带在海洋-大陆板块边界演化。

Some essential features of Andean orogenesis cannot be explained only by a dynamic regional model since there are essential influences across its vertical boundaries. A dynamic regional model of the Andes should be embedded in a 3-D spherical-shell model. Because of the energy distribution on the poloidal and toroidal parts of the creeping velocity and because of geologically determined mass transport alongside the Andes, both models have to be 3-D. We developed a new viscosity profile of the mantle with jumps at the lithospheric-asthenospheric boundary and at a depth of 410, 520 and 660 km. Therefore, the challenges to the code Terra are now essentially larger. In the last three years we have resolved these problems in an international cooperation (see 2.2 b)). Based on the new viscosity profile and on the improved Terra, we computed a new forward spherical-shell model [103, 104]. Papers on the improvement of Terra [56, 70] have been submitted. We conceived a regional model of the Andean orogenesis (3.2 b)) with the same new viscosity profile. We want to investigate why there is flat-slab subduction in some segments of the Andes and why deformation of the crust and volcanism migrate eastward. The evolution of the abundances of incompatible elements indicate a cycle which was finished by a fast process, perhaps by a large-scale delamination of the lower plate, perhaps also by another type of delamination. In connection with another spherical-shell model (with prescribed plate boundaries), the regional model should numerically explain why a plateau-type orogen evolved at an oceanic-continental plate boundary.