Seismic images of the core-mantle boundary

Seismology presents several ways of providing images of the geologic structures that exist in the lowermost mantle just above the core-mantle boundary (CMB). An understanding of the possibly complex geophysical processes occurring at this major discontinuity requires the combined efforts of many fields, but it is the role of seismology to geographically map out this largely uncharted territory. Seismic phases that reflect, diffract, and refract across the CMB can all be used to provide different information in different ways, as described in this paper. -from Author