Background data for: "Geodynamic Models of Late-Syn- to Post-rift Salt Tectonics on Wide Rifted Margins - Insights from Geodynamic Modelling"

Geodynamic Numerical model outputs (animations) of "Late-Syn- to Post-rift Salt Tectonics on Wide Rifted Margins - Insights from Geodynamic Modelling" (Tectonics, 2022) The geodynamic models of lithosphere extension and post-rift salt tectonics quantify different types of salt flow on rifted margins and test the effects of different salt viscosities (low, intermediate and high) on salt tectonics and margin evolution. The models show that updip extension balances largely with downdip diapir shortening, but that the distal salt nappe advance is largely unrelated to these processes. The salt nappes form by a combination of late syn-rift salt stretching and post-rift pressure-driven salt flow. This implies that the present-day width of salt nappes cannot be used as a constraint to balance updip extension on salt-bearing rifted margins. These observations have important implications for kinematic reconstructions of salt tectonics along rifted margins based on the common assumption of balanced salt deformation and for understanding the relationship between the distal edge of the salt basin and continent-ocean boundaries, important for plate-kinematic reconstructions. Salt tectonics in all models exhibits three characteristic phases. 1) Syn-depositional salt flow and development of syn-salt-deposition minibasins resulting from stretching in the distal margin as salt is deposited during the last phase of rifting. 2) Emplacement of distal salt nappes on the early oceanic crust by stretching above the rift axis. 3) Post-rift sediment progradation and significant salt tectonics in the form of updip extension, translation, downdip diapir shortening, and pressure-driven salt flow and nappe advance. The occurrence of these distinct deformation processes (e.g., updip extension, translation, downdip shortening, syn-rift nappe stretching and post-rift nappe advance) is independent of salt viscosity, however, their magnitude, timing, as well as the style of salt deformation, vary. Our models improve the current understanding of the dynamics of salt tectonics along rifted margins and the interplay between rifting and syn- to post-rift salt deformation associated with late syn-rift salt basins. The models are comparable to various examples of wide salt-bearing rifted margins such as the Brazilian, parts of West Africa, and Gulf of Mexico salt basins. They reproduce their observed crustal-scale architecture, regional salt tectonics styles, distribution of structural domains, and magnitudes of deformation.

地动力学数值模型输出（动画）：《晚期裂谷至后裂谷盐构造在宽裂谷边缘——地动力学模拟的启示》（构造学，2022年）。该地动力学模型量化了岩石圈伸展和后裂谷盐构造的不同盐流类型，并检验了不同盐粘度（低、中、高）对盐构造和边缘演化的影响。模型表明，上倾伸展与下倾地幔短缩在很大程度上保持平衡，但远端盐层前移与这些过程关系不大。盐层通过晚期裂谷盐拉伸和后裂谷压力驱动的盐流相结合而形成。这表明，盐层目前的宽度不能作为约束条件来平衡盐承载裂谷边缘的上倾伸展。这些观察结果对于基于常见平衡盐变形假设的裂谷边缘盐构造运动学重建具有重要意义，并且对于理解盐盆地远端边缘与大陆-海洋边界之间的关系，这对于板块运动学重建至关重要。所有模型中的盐构造均表现出三个典型阶段。1）沉积同期盐流和由于裂谷最后阶段沉积盐而导致的同期盐沉积小型盆地的形成。2）远端盐层在裂谷轴上方的早期海洋地壳上的就位，这是由于裂谷轴上方的拉伸作用。3）后裂谷沉积物前积和以上倾伸展、平移、下倾地幔短缩、压力驱动的盐流和盐层前移为特征的显著盐构造。这些独特的变形过程（例如，上倾伸展、平移、下倾短缩、同期裂谷盐层拉伸和后裂谷盐层前移）的发生与盐粘度无关，然而，它们的幅度、时间以及盐变形的风格却有所不同。我们的模型提高了对裂谷边缘盐构造动力学以及与晚期同期盐盆地相关的裂谷和同期至后裂谷盐变形之间相互作用的理解。这些模型可与巴西、西非部分地区和墨西哥湾盐盆地等宽盐承载裂谷边缘的多种实例相比较。它们重现了其观测到的地壳尺度结构、区域盐构造风格、结构域分布和变形幅度。