Quantified Cenozoic Shortening in the Kyrenia Range (North-Cyprus): The Effect of Plate Convergence and Tectonic Escape along the African-Anatolian Plate Boundary

Abstract

The Kyrenia Range is located on northern Cyprus in the eastern Mediterranean, an area dominated by the convergence between the African and Anatolian plates. The regional geology of this area is complex and evolved through different tectonic phases: subduction, collisional or transpressional deformation, subsidence and uplift in the Mesozoic-Cenozoic (Harrison et al., 2004; Calon et al., 2005; McCay&Robertson, 2013). Some researchers interpret the Kyrenia Range as transpressional feature, while others interpret it as a fold-thrust belt. Also the timing of faulting at the Kyrenia Range is controversial, ranging from deformation being active in the Eocene, Miocene, or Pliocene. This paper focusses on the different deformation events affecting the Kyrenia Range. Two major deformation events were detected: an extensional phase in the Cretaceous, and thrusting in the end of the Miocene. Also episodes of rapid (flexural) uplift and subsidence affected the Kyrenia Range, similar in style to the well-known deformation on Crete. The folding and thrusting at the Kyrenia Range resulted in 46 km of shortening and was dated as late Tortonian - early Messinian, based on age dating of calcareous nannofossils. The high amount of shortening at the Kyrenia Range, indicates that the convergence between Africa and Anatolia was entirely accommodated within the Kyrenia Range during the late Tortonian-early Messinian. During this time the Kyrenia Range was at the plate boundary between Africa and Anatolia. The structures on the Kyrenia Range indicate that the convergence was roughly N-S creating a fold-thrust belt, propagating southward. No transpressional deformation were detected. The shortening rate, is compared with the convergence rate of the Anatolia Plate with the African Plate. The timing and amount of shortening (2.3cm/y) indicates that the westward escape of Anatolia has resulted in an additional amount of convergence of 0.5cm/y (Kempler&Garfunkel, 1994). Only by including the westward escape of Anatolia the high shortening rate at the Kyrenia Range can be explained.