Delamination (geology)

Loss of the portion of the lowermost lithosphere from the tectonic plate to which it was attached

California's Sierra Nevada Mountains (formed by delamination) as seen from the International Space Station. When a large portion of dense materials was removed under the tectonic plate at this location, the remaining portion of the crust and lithosphere underwent a rapid uplift forming this mountain range.

In geodynamics, delamination refers to the loss and sinking (foundering) of the portion of the lowermost lithosphere from the tectonic plate to which it was attached.