Formation of mature lower crust, its flow and exhumation in the CAOB
The origin of lower crust in Central Asian orogenic Belt is generic question not answered in any accretionary systems in the world. The juvenile accretionary wedges are molten during roll back of oceanic subduction zones thereby forming large zones of partially molten material. The latter becomes redistributed underneath back arc oceanic crust during subsequent contraction events forming inverted density crustal profiles. The allochthonous lower crust is exhumed along giant migmatitic domes cored by juvenile plutons in Chinese and Mongolian Altai. The fascinating processes of cratonization of lower crust, its flow and final exhumation are studied using geophysics, petrology and structural geology.