Abstract

Metamorphism connected with the main growth and deformation stages of the Himalaya ranges from mid-Cretaceous to the Quaternary. Northward subduction gave rise in the early to mid-Cretaceous to an island are complex with greenschists, amphibolites, granulites and blueschists in the W (Kohistan-Ladakh) and an Andean-type margin with greenschist-amphibolite grade metamorphism in the E (India and Tibet). Ophiolitic nappes were thrust southwards over the Indian continental margin in the Palaeogene during the final stages of closure of the southern arm of Tethys. The Indus-Zangbo Suture bifurcates westwards and between the two sutures lies the Kohistan-Ladakh island arc which was converted to an Andean-type arc in the Palaeocene-Eocene. The Karakorum Range underwent northward subduction at least during the late Cretaceous to give rise to a complex and prominent calc-alkaline batholith. Post-collisional southward thrusting of crustal slabs over the Indian continental margin took place in the early Miocene with production of high-grade metamorphism, inverted isograds and crustal melt granites. Later southward thrusting in the Pliocene to Quaternary gave rise to localized low-grade recrystallization against the thrusts.

This content is PDF only. Please click on the PDF icon to access.

First Page Preview

First page PDF preview
You do not currently have access to this article.