Definition
The Structure of Earth’s core is referred to as the properties of velocity, density, attenuation, anisotropy, and composition of Earth’s core, and how these properties change with depth, geographic location, and time.
Attenuation is a measure of material’s ability to absorb energy as seismic waves pass through it.
Anisotropy is a material property that is directionally dependent.
Overall structure: The Earth’s core occupies the center portion of Earth with a radius of 3,480 km. It consists of a liquid outer core and a solid inner core. Earth’s core is composed of Fe/Ni and some minor light elements, such as S, C, O, and Si. Those light elements are preferentially enriched in the outer core. Seismic compressional velocity and density exhibit sharp jumps at the inner core boundary at the radius of 1,221 km. The inner core is anisotropic in both velocity and attenuation, with seismic waves exhibiting higher velocities and higher attenuation as they propagate along the polar...
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Wen, L. (2011). Earth’s Structure, Core. In: Gupta, H.K. (eds) Encyclopedia of Solid Earth Geophysics. Encyclopedia of Earth Sciences Series. Springer, Dordrecht. https://doi.org/10.1007/978-90-481-8702-7_150
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DOI: https://doi.org/10.1007/978-90-481-8702-7_150
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