A Paleomagnetic study on the tectonic evolution of the Nigde-Kirsehir massif and the Taurides since the Mesozoic-Cenozoic

The main tectonic domains of Turkey consist of several different assemblages of microcontinents represented by the Istranca massif, Istanbul Zone, Sakarya Zone, Nigde-Kirsehir Massif, Anatolide-Tauride block, and the Arabian platform. It is widely reported that the borders between these fragments are represented by suture zones, which resulted from the closure of different branches of the Neotethian Ocean. The northern suture zone, the Izmir-Ankara-Erzincan suture zone, is well known, whereas the suture zone between the Nigde-Kirsehir massif and the Taurides has been a subject of debate. It has been proposed that the Nigde-Kirsehir massif rifted from the Taurides-Anatolides in the Mesozoic and that the Intra-Tauride Ocean lay between these blocks. Other researchers have alternatively proposed that the Intra-Tauride Ocean between the Taurides-Anatolides and the Nigde-Kirsehir massif never existed, and assume that the it is a promontory of the Taurides. Paleomagnetic rotations obtained from a previous study indicate oroclinal bending in the Late Cretaceous in the northern part of the Nigde-Kirsehir massif due to its northwards indentation onto the Sakarya zone. However the southern deformation history of the Nigde-Kirsehir massif during Mesozoic has not been investigated. We have carried out a paleomagnetic study on the southern part of the massif, using a total of 120 sites that are of Late Jurassic to Miocene in age, to constrain the paleotectonic evolution of the Nigde-Kirsehir massif and its surrounding area. A paleolatitude of 17°N is obtained for the Late Jurassic-Lower Cretaceous Tauride carbonate platform, whereas Late Cretaceous arc volcanics from the suture zone around the Nigde-Kirsehir massif (Mersin ophiolite, Pozanti ophiolite) indicate a ~20°N paleolatitude. Both the Late Jurassic to Middle Eocene paleomagnetic declinations from the southeastern part of the investigation area indicates counterclockwise rotation, whereas Late Cretaceous declinations from the southwestern part, show rotations that are consistent with the curvature of the Neotethian suture zones.