Geomorphology of the Kapıdağ Peninsula and South Marmara Islands and its evolution in the quaternary

The study area of the Kapıdağ Peninsula and the South Marmara Islands constitute this thesis study area. In the book edit by "Marmara Takım Adaları (Bugünkü Arazi Kullanım Potansiyeli) Marmara Archipelago (Today's Land Use Potential) written by Tunçdilek et al., Which led our works in 1987, the book's geomorphology mentions many marine terrace localities and mapped them, but the lack of detailed information has directed us to the mentioned thesis area. Although it is in the form of unspoiled natural plain in the vast majority of marine terraces mentioned by Tunçdilek team; none of them had a marine warehouse. Despite all this, although they are located in different localities, all of their localities in Avşa, Koyun and Marmara islands have been separated from each other by forming a bedrock of metamorphic-based islands with a height of 3 - 4 m. This is an island where we see almost the same structural and lithological elements; It is also possible to see the shores of Kapıdağ terraces showing abundant fossiliferous depot character were named the Marmara Formation depo based on the studies conducted by Yaltırak and Sakınç et al in 2002. Aging of marine shells and shells that characterize the Marmara Formation was made by us and AMS 14C (Carbon 14) ages (calibrated): They indicate that they were formed at 70 cm below the surface in northeastern of Avşa Island, BC.1390-1240 years and BC.1560-1340 years; 1 meter deep; BC.1380-1300 years; 2 meters deep; BC.3960-3690 years; 230 cm deep in 3 different marine shells: BC.7150-6830 years, BC.7220-6930 years and BC.2360-2150 years; western side on the Koyun island 10 and 2 meters in two different levels, such as the between BC.6540-6370 years and BC.6950-6750 years. Looking at short distances, the age of these marine shells appears to be between 6950 and 1300 years before the present and indicate the Middle-Late Holocene period. vi The age of AMS 14C (Carbon14) made from shells in the deposit on the island of Hasır Island (calibrated), respectively; it should be a deposit with tsunamigenic character between 14 BC.2340 and 1870 years. The age of AMS C (Carbon14) made from the Ostrea edulis shells, which we found the beachrock within 2 meters of the sea level of the west coast of Hasır Island, is calibrated (respectively); be pointed at BC.2940-2730 years. At that time, the sea level is about 2 meters lower. Therefore, this 200 meters long beachrock-block was then drown by the sea; nowadays the west of the island extends parallel to the coast at 2 m submarine. The coasts of the Kapıdağ Peninsula and the South Marmara Islands are the youngest shores affected by active tectonics and drowned by the sea during the Middle-Late Holocene. Keywords: Marmara Formation, Terraces, Mid to Late Holosen Age, Ostrea Edulis vii