Collaborative Project: EaGER - CSEDI: Towards an integrated view of deep mantle structure, temperature, and composition

这项早期探索性研究基金（EaGER）将支持矿物物理学家和地震学家之间的一项合作研究，以尝试一种结合矿物物理学和地震学的新方法，为地球深部提供新的视角。从全球到局部尺度的地球深部地震成像技术的进步，正在提供有关下地幔对流和热模式的结构信息。发展第一性原理方法来解决关键的矿物物理问题，如热弹性性质、下地幔矿物中铁的自旋交叉和非调和热性质，极大地扩展了深部地幔条件下矿物性质的表征。这项工作的目标和主要知识价值是通过多学科的变革努力，将地震成像与基于真实矿物性质的建模方法直接联系起来，从而促进对深部地幔结构、温度和组成的理解。该团队将解决深层地幔温度和组成研究中尚未解决的核心问题：下地幔矿物中铁的自旋状态变化的微妙影响，以及对这种基本转变的潜在地震探测以及对下地幔整体化学的相应含义。澄清自旋态交叉地震特征是地球深部地震资料矿物学解释中需要克服的一个主要障碍。在深部地幔中寻找自旋跃变特征的提议并非没有风险，但这一史无前例的地震学/矿物物理学联合研究将为未来对众多迷人结构的研究铺平道路，这些结构掌握着深部地幔本质的关键。它将在这些社区之间开启必要的第一手对话，并使弹性数据能够在线访问，供地震学社区用于建模目的。这项研究的pi拥有不同的专业知识，这将有助于团队在地震学和矿物物理学之间的界面上培养多学科的教育经验。

This Early Grant for Exploratory Research (EaGER) will support a collaborative study between mineral physicists and seismologists to try a new approach of combining mineral physics and seismology to provide new perspectives of the deep Earth. Advances in seismic imaging of the Earth's deep interior, from global to local scales, are providing structural information about convective and thermal patterns in the lower mantle. Development of first principles methodologies to tackle key mineral physics problems, e.g., thermoelastic properties, spin crossover in iron in lower mantle minerals, and anharmonic thermal properties, are greatly expanding characterization of mineral properties at deep mantle conditions.The goal and primary intellectual merit of the proposed work is to advance understanding of deep mantle structure, temperature, and composition with a transformative multidisciplinary effort to directly link seismological imaging with modeling approaches based on realistic mineral properties. The team will address an unresolved central issue in investigations of deep mantle temperature and composition: the subtle effects of spin state changes in iron in lower mantle minerals and potential seismological detection of this fundamental transition and corresponding implications for bulk chemistry of the lower mantle. Clarification of the seismic signature of spin state crossovers is a major hurdle to be overcome in mineralogical interpretations of seismological data of the deep Earth. The proposed search for spin transition signatures in the deep mantle is not without risks, but this unprecedented joint seismology/mineral-physics enterprise will pave the way for future studies of numerous fascinating structures holding keys to the nature of the deep mantle. It will open a needed first-hand dialogue between these communities and enable elasticity data to be accessible online for use by the seismology community for modeling purposes. The PIs of this study have diverse expertise that will help the team to foster a multi-disciplinary education experience at the interface between seismology and mineral physics.