What do pallasite meteorites tell us about processes deep in the interior of differentiated planet(essimal)s?

理论和数值研究表明，外核区的化学不均匀性深刻地影响着地核和地幔的动力学和演化，以及地磁场的行为。然而，我们目前对这种异质性知之甚少。例如，地核-地幔边界的异常地震信号给出了最外层地核的地球化学不均一性的诱人迹象，但我们星球的这一区域绝不能进行直接的地球化学调查(尽管《地核》等电影会让你相信)。原子模拟对地幔最深处的化学成分提供了一些限制，地球物理模拟技术可以用来预测最外层核心内的地球化学不均质性。淡陨石陨石可能来自分化的行星体，在太阳系历史早期，这些行星体因与大星系的碰撞而破碎成碎片。这些陨石可能会提供间接证据，用来测试地球深处的过程。该项目将结合对苍白陨石陨石的地球化学调查、地球最外层核心成分的地球物理模拟和金属/硅酸盐平衡成分的原子模拟，调查苍白陨石陨石的性质和来源，以及它们所包含的有关行星体分异过程的哪些信息。

Theoretical and numerical studies indicate that chemical heterogeneity in the outer core region profoundly influences the dynamics and evolution of Earth's core and mantle, and the behaviour of the geomagnetic field. However, we presently don't know much about this heterogeneity. For example, tantalizing hints of geochemical heterogeneity in the outermost core are given by anomalous seismic signals at the core-mantle boundary, but this region of our planet is by no means accessible for direct geochemical investigation (despite what movies such as "The Core" would have you believe). Atomistic modelling provides some constraints on what chemical composition could be expected in the deepest portions of the mantle and geophysical modelling techniques can be used to predict geochemical heterogeneity within the outermost core. Pallasite meteorites may be derived from differentiated planetesimals, subsequently smashed into fragments by collisions with large bolides early in the history of the solar system. These meteorites may provide indirect evidence with which processes deep within the Earth can be tested. This project will use a combination of geochemical investigations of pallasite meteorites, geophysical modelling of the composition of the Earth's outermost core and atomistic modelling of equilibrium metal / silicate compositions to investigate the nature and origin of pallasite meteorites and what information they contain regarding differentiation processes in planetary bodies.