Sidao Ni

Abstract Ultralow velocity zones revealed by seismological observations at the core–mantle boundary lend clues to the physico-chemical characteristics and dynamic evolution of the Earth’s deep interior. Ultralow velocity zones have been primarily detected within and at the edges of the large low-velocity provinces. Ultralow velocity zones in high-velocity lowermost mantle have also been reported, but global assessment has been limited by data coverage.

Abstract The fine-scale seismic features near the inner core boundary (ICB) provide critical insights into the thermal, chemical, and geodynamical interactions between liquid and solid cores, and may shed light on the evolution mechanism of the Earth’s core. Here, we utilize a dataset of pre-critical PKiKP waveforms to constrain the fine structure at the ICB, considering the influence of various factors such as source complexity, structural anomalies in the mantle, and properties at the ICB.

Report View ORCID ProfileWenbo Wu1,*, View ORCID ProfileZhongwen Zhan1, View ORCID ProfileShirui Peng1, View ORCID ProfileSidao Ni2, View ORCID ProfileJörn Callies1 1Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, USA. 2State Key Laboratory of Geodesy and Earth’s Dynamics, Institute of Geodesy and Geophysics, Chinese Academy of Sciences, Wuhan 430077, China. ↵*Corresponding author.