Understanding how Earth's inner core (IC) develops and evolves, including fine details of its structure and energy exchange across the boundary with the liquid outer core, helps us constrain its age, relationship with the planetary differentiation, and other significant global events throughout Earth's history, as well as the changing magnetic field. Since its discovery in 1936 and the solidity hypothesis in 1940, Earth's IC has never ceased to inspire geoscientists. However, while there are many seismological observations of compressional waves and normal modes sensitive to the IC's compressional and shear structure, the shear waves that provide direct evidence for the IC's solidity have remained elusive and have been reported in only a few publications. Further advances in the emerging correlation-wavefield paradigm, which explores waveform similarities, may hold the keys to refined measurements of all IC shear properties, informing dynamical models and strengthening interpretations of the IC's anisotropic structure and viscosity.

了解地球内核 (IC) 是如何发展和演化的，包括其结构的细节以及与液体外核边界的能量交换，有助于我们限制其年龄、与行星分化的关系以及地球历史上其他重要的全球事件，以及不断变化的磁场。自 1936 年发现和 1940 年提出固体假说以来，地球的 IC 从未停止对地球科学家的启发。然而，虽然有许多对 IC 的纵波和横波结构敏感的纵波和法向模式的地震学观测结果，但为 IC 的坚固性提供直接证据的横波仍然难以捉摸，并且仅在少数出版物中进行了报道。新兴的相关波场范式的进一步进展，