In the Boyali area, northern Turkey, the tectonic units of the Istanbul-Zonguldak Terrane and the IntraPontide suture zone are thrust over the deposits at the top of the Sakarya Terrane, known as Tarakli Flysch. It consists of Early Maastrichtian-Middle Paleocene turbidite and mass-gravity deposits, whose source mainly corresponds to the Istanbul-Zonguldak Terrane, and, with a lesser extent, to the IntraPontide suture zone. These deposits were sedimented in a foredeep basin developed during the convergence between Sakarya and Eurasian continental microplates. In the Late Paleocene-Early Eocene time span, the Tarakli Flysch was deformed (D1 phase) during the closure of the foredeep basin. In the Miocene time, the strike-slip tectonics (D2 phase) related to the North-Anatolian fault produced further deformations of the Tarakli Flysch. (C) 2013 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved.