Two-stage development of the Late Cretaceous to Late Eocene Darende Basin: implications for closure of Neotethys in central eastern Anatolia (Turkey)

The Darende Basin is an excellent example of an important, but little known, type of sedimentary basin that can form on the top of emplaced ophiolites prior to and during continental collision. The basin formation was preceded by southward emplacement of accretionary mélange and ophiolites onto the Tauride carbonate platform during latest Cretaceous. Sedimentation began during the Maastrichtian with non-marine clastic sediments accumulating in palaeovalleys. This was followed by a Maastrichtian marine transgression, triggered by extension along the basin margins. Rudist-rich patch reefs and a carbonate shelf developed in different areas. A second transgression during the Mid-Eocene was preceded by emergence, a hiatus (Paleocene), localized faulting and low-angle (<5–10°) tilting. Middle Eocene hemipelagic marls, shallow-marine Nummulites-rich carbonates, calciturbidites and sparse alkaline volcanism culminated in Late Eocene shallowing, emergence and then deformation. The first phase of basin development (Maastrichtian) is seen as extensional, related to slab-pull that resulted from northward subduction of remnant oceanic lithosphere beneath Eurasia in the Pontides to the north. The second phase of basin development (Mid–Late Eocene) is explained by crustal downflexure to form an under-filled foreland basin during the final collision of the Tauride continent with Eurasia. Basin uplift was delayed until after a Mid-Miocene marine incursion.