Inverse and forward multiscale numerical modeling of the Alpine orogeny (IFMMALPO)

高山造山运动的反演和正演多尺度数值模拟 (IFMMALPO)

• 批准号: 365286839
• 负责人: Dr. Alexey Petrunin
• 金额: --
• 依托单位: Department 1: Geodäsie
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2017
• 资助国家: 德国
• 起止时间: 2016-12-31 至 2020-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/365286839?language=en
• 关键词: Inverse; forward; multiscale; numerical; modeling

The Alps is a part of Alpide mountain belt formed as a result of the collision of the African and Eurasian plates during the Cenozoic Era. This collision formed a compound tectonic structure characterized by complex geology. Numerical modeling of the collision process leading to the Alps formation might be a key to our understanding of tectonic processes accompanying the Alpine orogeny. Nevertheless, only few 2D numerical models for this region are known to date. These models consider deformation processes in the lithosphere, neglecting influence of the mantle flow and 3D far-field stress originated from the large scale plate motion. To better understand how the mantle flow affects the lithospheric and crustal deformation during Alps formation since Early Cenozoic, a model of the relative plate motion in a larger scale in 3D is required. However, it is not obvious how the heterogeneity of density and viscosity in the mantle can be related to plate motion and deformations in the lithosphere. The initiation of a forwards-in-time modelling of the plate motion in a past based on present-day knowledge of the mantle structure is also an issue because of several reasons such as an irreversible thermal diffusion and incomplete geophysical dafta for the Alps. To overcome these problems, we are going to use the latest methods and data provided by cooperation within the SPP 4D-MB project that will give us a possibility to create an inverse-in-time large-scale model of the whole-mantle convection during Cenozoic with a focus on the collision of the African and Eurasian plates and for the first time simulate in 3D+time the Alpine orogeny, using the results of the global mantle convection model as an initial an temporary varying boundary conditions. The IFMMALPO project will use the data from the seismic networks (AF-A,B,C,D), geological studies (AF-E) and contribute to the current and next stages of the SPP 4D-MB providing data on the structure, tectonic evolution (RT1, RT3), and the stress state of the lithosphere and mantle in the Alpine region (RT2, RT4).

阿尔卑斯山是新生代非洲板块和欧亚板块碰撞形成的阿尔卑斯山带的一部分。这次碰撞形成了地质复杂的复合构造。碰撞过程的数值模拟导致阿尔卑斯山的形成可能是我们理解伴随阿尔卑斯造山运动的构造过程的关键。然而，迄今为止，该地区只有少数二维数值模型是已知的。这些模型考虑了岩石圈的变形过程，忽略了地幔流和大尺度板块运动产生的三维远场应力的影响。 为了更好地理解早新生代以来阿尔卑斯山形成过程中地幔流动对岩石圈和地壳变形的影响，需要一个更大尺度的三维板块相对运动模型。然而，地幔中密度和粘度的不均匀性如何与岩石圈中的板块运动和变形联系起来还不明显。由于不可逆的热扩散和阿尔卑斯山不完整的地球物理数据等原因，根据目前对地幔结构的了解，对过去的板块运动进行时间向前模拟也是一个问题。为了克服这些问题，我们将使用SPP 4D-MB项目合作提供的最新方法和数据，这将使我们有可能创建新生代全地幔对流的逆时大尺度模型，重点关注非洲和欧亚板块的碰撞，并首次在3D+时间内模拟阿尔卑斯山脉，利用全球地幔对流模式的结果作为初始和临时变化的边界条件。IFMMALPO项目将使用来自地震网络（AF-A、B、C、D）和地质研究（AF-E）的数据，并为SPP 4D-MB的当前和下一阶段提供有关阿尔卑斯地区的结构、构造演化（RT 1、RT 3）和岩石圈和地幔应力状态（RT 2、RT 4）的数据。