Influence of Earth's rotation on the differentiation of a terrestrial magma ocean

在地球吸积的后期，地球经历了一次或多次火星大小的撞击，导致形成一个或几个全球范围的深岩浆海洋。这些岩浆海洋的结晶对于地球的化学结构和板块构造的开始至关重要。 由于早期地球的快速旋转和岩浆粘度小，旋转可能对分异过程产生了深远的影响。然而，几乎所有以前的研究都忽略了旋转的影响。在我们以前的工作中，在一个单位正方形，我们表明，旋转有一个重要的影响岩浆海洋动力学。据我们所知，目前还没有其他模型可以包含旋转力。在本提案的范围内，我们计划将我们开发的方法扩展到现实的球形几何形状，以研究旋转对陆地岩浆海洋结晶的影响球壳。此外，我们将研究岩浆海洋相关的流变学和不同矿物相之间的相互作用。另一个关键方面将是旋转和强烈对流的岩浆海洋顶部不同类型大气的影响，我们计划通过在顶部应用不同的边界条件来研究。据我们所知，类似的调查还没有进行过其他小组。我们认为，拟议的工作可以提供从根本上新的见解，陆地岩浆海洋的分异过程，从而阐明的创造和生存的组成水库。特别是起源，分布和持续性的非均匀性相对于大的低切变速度省（LLSVP）将进行调查。这些结构对于板块构造的开始和演化以及磁场的时间历史都很重要，因此与地球的可居住性密切相关。

In a later stage of its accretion Earth experienced one or more giant impacts of mars-sized impactors, causing the formation of one or several deep magma oceans of global extent. The crystallization of these magma oceans is of key importance for the chemical structure of Earth and for the onset of plate tectonics. Due to the fast rotation of early Earth and small magma viscosity, rotation probably had a profound effect on differentiation processes. However, nearly all previous studies neglected the effects of rotation. In our previous work, obtained in a unit square, we showed that rotation has an important influence on magma ocean dynamics. To our knowledge there is currently no other model available allowing to include rotational forces.Within the scope of this proposal we plan to extend our developed method to a realistic spherical geometry in order to investigate the influence of rotation on the crystallization of a terrestrial magma ocean in a spherical shell. Further, we will study magma ocean-relevant rheology and the interaction between different mineral phases. Another key aspect will be the influence of different types of atmospheres at the top of a rotating and vigorously convecting magma ocean, which we plan to study by applying different boundary conditions at the top. To our knowledge similar investigations have not yet been carried out by other groups.We feel that the proposed work can provide fundamentally new insights into differentiation processes of a terrestrial magma ocean and thus shed light on the creation and survival of compositional reservoirs. Especially the origin, distribution and persistence of heterogeneities with respect to large low shear velocity provinces (LLSVP) will be investigated. These structures are important for the onset and evolution of plate tectonics as well as for the time-history of the magnetic field, thus being closely linked to the Earth's habitability.