Abstract: The sequence ranges from Precambrian to upper-most Cainozoic in the investigated area.Their total thickness is about 12000 meters. Units of Precambrian age consist of mctabasîc, amphibolitesand banded gneisses and they crop out on Kaplandededağ and Sünicedağ. Paleozoic units have two depositional periods. The first period begins in Cambrian and ends at the beginnig of Silurian with a regression. The second one begins in Silurian with a transgression and end in Upper Carboniferous with a regression. In Çamdağ area, rock of Devoian age begin with a transgression and overlie rocks of, Ordovician-Lower Silurian age with an angular unconformity. In Kaplandedcdağ-north of Düverdüzü Village, rocksof Upper Cambrian-Lower Ordovician overlie the units of Precambrian age with a primary stratigraphie contact. Ordovician units arc composed of red mudstones, siltones and conglomerates. Black shalesof Silurian age interbedded with bluish black limes to nes overlie the Ordovician and Lower Silurian sediments with an angular unconformity. The contact, between Silurian and Devonian is concordant and/ortransitional* Devonian-Carboniferous boundary is tra nsitional in the Zonguldak subarea, Middle-Upper Carboniferous deposists do not crop out in the investiga ted area, because of Precambrian and Lower Paleozoic uplifts, Permotriassic sediments which were de posited in continental and near shore-shallow marineenvironments overlie older sediments with an angular unconformity. The Upper Jurassic and LowerCretaceous rocks overlap the uplift taking place in eastern part of Ereğli-Dikmentepe Hill and do notextend westwards. Island arc volcanic activity which belongs to north dipping Neotethyan subduction zone, started in Cenomanîan and ended in Eocene, Sediments of Eocene age begin with angular unconformity and show different fades in investigation area. Continental rock units were deposited duringPliocene in the region which was eroded during Oli go-Miocene.Gi^anitoids and diabasic rocks which are older than Upper Jurassic crop out around Orhandağ andSünnİcedağ Mountains.