Continental Crustal Evolution
Shanan E. Peters
Abstract
The Earth is unique among the terrestrial planets in having well evolved crustal material. Despite the importance of continental crust to geological processes, comparatively little is known about its origin and evolution. It is generally accepted that evolved crustal material has been generated by partial intracrustal melting to give an overall andesitic composition. The decrease in heat generation of radiogenic isotopes over geologic time has led to the thickening of the lithosphere and thinning of the oceanic crust. A possible model for crustal evolution involving granitic ophiolite generation during the interval 1.5-2.0 Ga is also proposed.