The Himalayas—a modern analogue for Archaean crustal evolution

Abstract

Present crustal evolution models fail to account for the generation of the large volumes of continental crust in the required time intervals. If the oceanic crust was appreciably thicker in the Archaean, as geothermal models would indicate, then oceanic crustal collision on the scale of the present-day Himalayan continental collision zone may have been a frequent occurrence in the Archaean, resulting in extensive partial melting of the hydrous underthrust oceanic crust to produce voluminous tonalite melts leaving a depleted stabilised basic residuum.