Middle Carnian Arc-Type Basalts from the Lycian Nappes, Southwestern Anatolia: Early Late Triassic Subduction in the Northern Branch of Neotethys

Abstract

AbstractThe Turunc Unit, which represents one of the tectonic slices within the Lycian Nappes in southwestern Anatolia, preserves the remnants derived from the northern branch of Neotethys. The unit includes basalts intercalated with pelagic limestones of middle Carnian age (early Late Triassic) based on the characteristic radiolarian assemblage of the Tetraporobrachia haeckeli Zone. The Turunc lavas reflect trace element signatures resembling those from subduction zones, displaying selective enrichment of Th and light rare earth elements over high-field strength elements and heavy rare earth elements. Considering the overall geochemical characteristics of the Turunc basalts and given that they are found to be associated with no continent-derived detritus, the Turunc lavas appear to represent fragments of a Late Triassic island arc formed on the Neotethyan oceanic lithosphere. This result is of particular importance, since it reflects the oldest subduction age obtained from the entire Neotethyan realm to ...