mantlecrustal

Mantlecrustal is an adjective used in geology and geophysics to describe processes, materials, and structures that involve both the Earth's mantle and its crust, particularly at or near the crust–mantle boundary. The term emphasizes interactions across the Moho (the Mohorovičić discontinuity) and the transition between mantle-derived materials and crustal rocks.

Mantlecrustal processes include magmatic differentiation where basaltic magmas formed in the mantle ascend and crystallize in the crust, leading to crustal contamination and chemical signatures bridging mantle and crustal reservoirs. They also appear in tectonic settings such as subduction zones, where mantle rocks may be exhumed or mixed with crustal components, and in mantle xenoliths carried to the surface by magma. Ophiolites are classic examples of mantlecrustal sequences that record upper mantle peridotites overlain by crustal gabbros and basaltic crust.

Studying mantlecrustal interactions helps reconstruct the growth of continental and oceanic crust, the thermal evolution of the lithosphere, and the geochemical evolution of Earth. The concept encompasses lithospheric mantle participation in crust formation, crustal metasomatism by mantle-derived fluids, and the dynamic coupling between the crust and underlying mantle.

Because 'mantlecrustal' is not a strictly standardized term, scientists often phrase discussions in terms of mantle–crustal interactions, mantle contributions to crustal composition, or mantle rocks at the crustal level.