Abstract: The rock units in the study area have been divided mainly in  two groups as autochthonous and allochthonous. The Cretaceouscarbonate rock sequence is the oldest autochthonous rock unit in this region. The carbonate sequence consists of two units. Theseare in ascending order from bottom to top; (I) Söbüdağ formation (Cenomanian-Turonian), and (2) Senirce formation (Middle Maastrichlian). All Cretaceous rock units are overlain unconformably by Tertiary detritic sediments. The Tertiary sedimentary sequence has been divided in two units. These are from bottom to top; (I) The Kizilkirma formation is Upper Paleocene-Lower Eocene inage and (2) The Kayıköy formation is Middle Eocene in age. The Gölcük volcanism was active in the region during the Late Miocene to Early Pliocene period. The Gölcük formation is originated from the Gölcük volcanic materials. The Quaternary alluvium andalluvial-fan deposits are the youngest units for the study area. The Gökçebağ ophiolithic melange and Akdağ limestone units (Jurassic Cretaceous) are the allochthonous rocks in this region. Tliese allochthonous rocks were primarily emplaced in the region duringLate Cretaceous to Early Paleocene period. In the study area, the common tectonic structures such as reverse, overt hrust faultsand fold axis are extending along the NW-SE direction. On the other hand, the dominant normal faults and fracture systems aretrending along the NE-SW direction. It is possible that all these structural features in this region resulted under the NE-SW compressional forces, and NW-SE tensional forces.