Overview of magmatism in Northwestern Vietnam

Abstract

Amalgamation of tectonic plates of Southeast Asia occurred in northwestern Vietnam. Six groups of magmatic rocks are related to the tectonic events. The first group corresponds to the major episodes of crustal formation in the South China block, or is linked with the formation of Gondwana. The second group includes granitoids in connection with the collision and formation of the Caledonian-Hercynian folding event. The third group contains Upper Permian ophiolites, as well as the Permian extrusives, formed in intraplate setting, related to back-arcs spreading. The fourth group is related to Triassic Indosinian orogeny, the fifth group comprises Jurassic-Cretaceous intraplate granitoids. Finally, during Cenozoic times, magmatic rocks were represented by alkaline granitoids - the effect of strike-slip faulting related to the collision of India and Eurasia plates.