Akademik Veri Yönetim Sistemi
Geological Society Special Publication, cilt.425, sa.1, ss.189-212, 2016 (SCI-Expanded, Scopus)
© 2016 The Author(s).The Sakarya Zone and the Kirşehir Block of northern Turkey are separated by the Izmir-Ankara-Erzincan Suture (IAES) Zone which is the remnant of the northern branch of the Neotethys Ocean. During the closure of the IAES in the Late Cretaceous, northwards drift of the Kirşehir Block and its eventual indentation into the Sakarya Zone produced crustal deformation defined by thrusts and reverse faults, mainly between the indenting Kirşehir Block and the Sakarya Zone. Previous palaeomagnetic studies in the eastern part of the Pontides and the Sakarya Zone showed that palaeomagnetic declinations could record the deformation that resulted in the curvature of the IAES. In order to define the tectonic deformation of the northern part of the Kirşehir Block, we present new palaeomagnetic data from 57 different sites that include Mesozoic-Cenozoic sedimentary and volcanic rocks. The results from Late Cretaceous rocks (40 sites) indicate that large clockwise rotations of c. 140-165° occurred in the eastern limb of the bend, while anticlockwise rotations progressively decreased from c. 80° to 55° from SW to NW in the western limb of the bend. In contrast, small clockwise and anticlockwise rotations are observed in the flat-lying segment of the suture zone. These rotation patterns are consistent with the geometrical trends of the IAES in northern Turkey. Declinations of seven different Middle Eocene sites within the Kirşehir Block are rotated anticlockwise by c. 30-10°. This indicates that the deformation in the Sakarya Zone and the Kirşehir Block continued in the Middle Eocene.