Paleomagnetic results along the Bitlis-Zağros suture zone in SE Anatolia, Turkey: Implications for the activation of the Dead Sea Fault Zone

Abstract

The tectonic evolution of SE Anatolia is associated with the collision between the Taurides and the Arabian Platform in the early Cenozoic, after the final closure of the southern branch of the Neotethys ocean during Late Cretaceous to Early Eocene times. The ongoing deformation was characterized by northward movement of Arabia, followed by westward extrusion of Anatolia, having been displaced along the northern and eastern Anatolian transform faults. The neotectonic deformation history between the Anatolian Plate and the Arabian platform since the closure of the southern Neotethyan oceanic basin from Late Cretaceous to present has not been studied in detail paleomagnetically. Therefore we carried out a paleomagnetic study of Mesozoic and Cenozoic rocks at 34 localities along the Bitlis-Zağros suture zone in SE Anatolia located in the boundary region between the Taurides and the Arabian platform and delimited by the Dead Sea Fault.Paleomagnetic results from the area show clockwise rotations of 35.6° ± 14.1° and 26.7° ± 8.0° with respect to the African plate from Upper Jurassic - Lower Cretaceous and Upper Cretaceous limestones, respectively. The paleomagnetic results indicate also an earlier deformation/opening due to the Dead Sea Fault Zone (DSFZ). Farther north on the Tauride Block, counterclockwise rotation of −34.5° ± 12.5° is recorded by Upper Cretaceous limestones. In the SE of the study area on the northern margin of Arabia, however, smaller counterclockwise rotations of -12.3° ± 8.3° and −2.5° ± 10.0° in Late Cretaceous and −12.7° ± 13.6° in middle Eocene rocks show relative tectonic stability. Middle Miocene rocks close to the suture zone show counterclockwise rotation by about −39.4° ± 10.9°, while farther away from the suture zone counterclockwise rotations of −21.9° ± 9.9° and −7.5° ± 5.8° are observed. Paleolatitudinal motion from south to north from the Late Jurassic to the Present is in concordance with the apparent polar wander path of Eurasia and Africa.