The study of the Campanian-Ypresian planktonic foraminiferal biostratigraphy in two surface sections including three different formations in the A degrees zmit region. These formations begin at its Akveren Formation, consisting of Late Campanian-Selandian deep shelf and deep marine deposits. The deep shelf turbidites of the AtbaAYA +/- Formation were deposited during the Selandian-Ypresian, whereas the Ypresian is characterized by shallow shelf-type deposits of the Caycuma Formation. A total of 14 planktonic foraminifera biozones have been identified. The defined planktonic foraminiferal biozones from older to younger are Pseudoguembelina palpebra Partial-range Zone, Racemiguembelina fructicosa Partial-range Zone, Abathomphalus mayaroensis Partial-range Zone, Pseudoguembelina hariaensis Partial-range Zone, Parvularugoglobigerina eugubina Taxon-range Zone (P alpha), Parasubbotina pseudobulloides Partial-range Subzone (P1a), Subbotina triloculinoides Lowest Occurrence Subzone (P1b), Globanomalina compressa/Praemurica uncinata Lowest Occurrence Subzone (P1c), Praemurica uncinata Lowest Occurrence Zone (P2), Morozovella angulata Lowest Occurrence Zone (P3), Globanomalina pseudomenardii Taxon-range Zone (P4), Morozovella velascoensis Partial-range Zone (P5), Pseudohastigerina wilcoxensis/Morozovella velascoensis Concurrent-range Zone (E2), Morozovella marginodentata Partial-range Zone (E3).