Seismic insights into Earth's core

Abstract

The inner and outer cores are the most remote layers of Earth, yet have wide-ranging impacts on its evolution. Here, we detail current structural models of the core, deliberate dynamic interpretations, and highlight limitations and potential targets for future research to address.

Fig. 1. Stylised illustration of structures and processes in Earth’s core.

The outer core radius is 3480 km, the inner core radius is 1220 km (to the nearest 10 km)³. Features denoted include: outer core stratification (the E’ and F- layers); inner core boundary topography and asymmetry of the F-layer; inner core hemispheres, anisotropy, and regional variation; and innermost inner core, distinctly different from the rest of the inner core. Arrows indicate the release of light elements upon inner core growth, colours and textures in the inner core signify the strength and nature of anisotropy, and shading in the outer core represents seismic velocity anomalies.