Internal evolution and magnetic field generation in rocky planets

我的研究包括地核动力学，以及分析太阳系以外具有不同质量和铁含量的岩石行星（即系外行星）上磁活动的演变和寿命。我关注的是地核的一个特定边界层，即所谓的f层。利用与地震学、矿物物理学和地球动力学相关的现有知识，我已经建立了一个模型，评估了几种地核二元成分与当前地震观测相匹配的可行性，以及它们对地核动力学的影响。该研究已在多个会议上发表（AGU, JpGU）。这项研究的主要发现是，碳和硫可能不是地核中主要的合金成分，而硅和氧是两个潜在的候选成分。它们在地核中的优势为液态外核对流的驱动力提供了有趣的暗示，在氧气存在的情况下，对流是热起源，在富含硅的地核中，对流是由化学浮力驱动的。我还开发了一个代码来描述具有不同质量和铁含量的岩石行星核心的热演化。该代码已被用于分析吸积后的行星核心结构，以及磁场的演变和寿命，并被地球物理研究杂志：行星接受。这项研究的主要发现是，体积和地幔铁含量都强烈地决定了岩石行星的磁场寿命。

My research consists of dynamics of Earth’s core, and the analysis of the evolution and longevity of magnetic activity on rocky planets beyond the solar system (i.e., exoplanets) having different masses and iron contents. I have focused on a specific boundary layer of Earth’s core, the so-called F-layer. Using current knowledge related to seismology, mineral physics, and geodynamics I have put together a model assessing the feasibility of several binary compositions of Earth’s core in matching present seismic observations, as well as their implications on the dynamics of Earth’s core. This study has been presented at several conferences (AGU, JpGU). The main finding of this study is that carbon and sulfur are likely not present as major alloying components in Earth’s core, whereas silicon and oxygen are two potential candidates. Their predominance in Earth’s core provides interesting implications for the driving force of convection in the liquid outer core, which is of thermal origin in the presence of oxygen and driven by chemical buoyancy for a silicon-rich core.I also developed a code describing the thermal evolution of the cores of rocky planets having different mass and iron content. This code has been used to analyze planetary core structures after accretion, as well as the evolution and lifetime of a magnetic field, and accepted to Journal of Geophysical Research: Planets. The main finding of this study is that both the bulk and mantle iron content are strongly determining the magnetic field lifetime of rocky planets.