The first record of the “Mid-Barremian” Oceanic Anoxic Event and the Late Hauterivian platform drowning of the Bilecik platform, Sakarya Zone, western Turkey

► Drowning of the carbonate platform in Late Hauterivian is recorded in western Turkey. ► The mid-Barremian OAE is recorded after the drowning event over the same platform. ► δ13C and δ18O isotope excursions display parallel pattern with European sections.