Models of Flow and Geochemical Transport in the Earth

[9814666]奥康奈尔提议的研究是研究由对流和板块构造引起的地幔中的流动和化学运输。地震构造和大地面线的地球物理观测与洋中脊和洋岛玄武岩同位素的地球化学观测对地幔结构的推断不一致。这是我们对地幔动力学和演化的理解中的一个主要差异。这项工作将包括计算简单对流系统中的质量传输、搅拌和变形，这些系统包括岩石圈板块运动、板块几何形状的演变、粘度随深度的变化以及流变非均质性。拟议的工作将评估这些影响，并评估这些过程能够解释各种地球物理和地球化学观测结果的可能性。

9814666 O'Connell The proposed research is to study flow and chemical transport in the mantle resulting from convection and plate tectonics. It is motivated by the discordant inferences about mantle structure from geophysical observations of seismic structure and the geoid, and geochemical observations of isotopes in basalts at mid-ocean ridges and ocean islands. This is a major discrepancy in our understanding of mantle dynamics and evolution. The work will involve the calculation of mass transport, stirring and deformation in simple convective systems that incorporate lithospheric plate motions, evolution of plate geometry, viscosity variations with depth, as well as rheological heterogeneities. The proposed work will evaluate these effects and assess the likelihood that such processes can account for the diverse geophysical and geochemical observations.