Up the down escalator: the exhumation of (ultra)-high pressure terranes during on-going subduction.

The article presents a study on the exhumation mechanisms of high and ultra-high pressure rocks in a tectonic environment during the subduction of continental crustal material. It says that buoyant continental crust must remain attached to a stronger substrate in order to subduct, whereas it must detach and be buoyant in order to exhume. Furthermore, it notes that exhumation may occur once in a specific orogen or subduction zone, or may occur in multiple times.