Geochemistry and petrology of NE Naragh volcanic rocks: island arc or active continental margin magmatism?

Abstract

The tectonic settings for the Urumieh-Dokhtar volcanic-plutonic belt provided by different reaserchers including active continental margin rift and post collisional settings. Geochemical and tectonic studies indicate that this belt belongs to the active continental margin. Basaltic andesite, andesite, trachy andesite, trachy dacite and dacitic rocks in NE Naragh, of the Urumieh-Dokhtar magmatic arc, Eocene in age, show some affinities to the volcanic island arc, in terms of geochemistry of major and trace elements. In comparison with the island arcs (e.g. Marianna) and active continental margin (e.g. the Andes), these rocks demonstrate intermediate characteristics. Specific tectonic setting and low thickness of the lithosphere of Central Iran during subduction of the Neo-Tethyan oceanic crust, is the main reason that resulted in the NE Naragh volcanic rocks with geochemical similarities to the island arcs.

Keywords


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