The inner core was discovered in 1936 by the Danish seismologist Inge Lehmann (1888–1993) from the observation of short‐period P‐wave arrivals in the shadow zone of the core, at a distance where no P‐wave would arrive if the core was totally fluid. Since her discovery, major advances concerning the structure of the inner core have been made thanks to seismological studies, combined with observational and computational results in mineral physics. A good knowledge of inner core structure is important to specify the chemical and mineralogical nature of the iron alloy which constitutes the center of the Earth, and to constrain the Earth's differentiation process. It also has important outcomes for the thermodynamical and geodynamical properties of the Earth.
Investigation tools: seismic waves and normal modes
The structure and properties of the inner core are mostly constrained by two body waves: PKIKP, a P‐wave transmitted through the inner core, and PKiKP, a P‐wave reflected at the inner...
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Souriau, A. (2007). Inner Core Seismic Velocities. In: Gubbins, D., Herrero-Bervera, E. (eds) Encyclopedia of Geomagnetism and Paleomagnetism. Springer, Dordrecht. https://doi.org/10.1007/978-1-4020-4423-6_153
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