coresmantle

Coresmantle is a term that is not standard in mainstream geophysics. It is sometimes used as a hypothetical or shorthand label for a region that blends properties of a planetary core and mantle, typically associated with or near the core–mantle boundary. Because it is not widely adopted in scientific literature, its meaning can vary between authors and contexts.

In Earth science, the core–mantle boundary (CMB) separates the liquid iron–nickel outer core from the solid lower mantle, at a depth of about 2,900 kilometers. The CMB is a critical interface for heat transfer, seismic wave propagation, and the dynamics of mantle convection and the geodynamo. When referred to as coresmantle, the term is often invoked to discuss transitional or mixed-chemistry concepts that lie between the pure core and pure mantle models, such as regions of partial melting, chemical heterogeneity, or altered seismic properties.

Interpretations of coresmantle in speculative or model-building contexts may include a thick transitional layer with graded composition, a zone of gradual rather than abrupt change from core-like to mantle-like materials, or a region where core and mantle processes interact more directly. In planetary science and science fiction, coresmantle can serve as a conceptual device to describe internal architectures that influence tectonics, volcanism, and magnetic phenomena.

See also: core–mantle boundary, inner core, outer core, mantle, D″ layer, geophysics, planetary differentiation.