ABSTRACT
There are various valley types in the rock groups formed from Ordovician to Miocene at the mouth of the Göksu River. Basement rocks in the area are composed of mainly low resistant Miocene mudstone-shale-marl and high resistant chalk arenites and middle or lesser amount of low resistant Ordovician metamorphic rocks; medium to high resistant Upper Devonian-Upper Cretaceous clastic and carbonaceous rocks. The types of valley with wide and broad floor is dominant in the Langhian-Tortonian low resistant mudstone-shale-marl-clayey limestone cropped out in the Mut town and surrounding area. These rock groups have slightly undulated morphology and low dipping strata. The deposition of the thick alluvial materials at the bottom of the Göksu River has led the developing of the many small planes along the Göksu Valley. A canyon valley in 5 km long was also developed in the Miocene chalk arenites showing plentifull joints and strongly porous nature that were observed in the Evkafçifitliği and Kargıcak villages at the central part of the study area. A very thin alluvial cover composed of pebbles-sands and muds was deposited at the bottom of the canyon. The valleys developed on the Paleozoic-Mesozoic clastic and carbonaceous rocks in the main valley of the Göksu River at the surrounding area of the Deðirmendere and Karkaya villages in the western part of the Silifke are narrow floor, anticline, syncline and cutting through type valleys. Terrace deposits are clearly observed in the main valley slopes while recent alluvial materials deposited in the bottom of the valley are in the shape of narrow and thin strips. The meander valley types have been occurred in the Langhian-Tortonian mudstones-shales-marls and and very thick Holocene alluviums showing a very wide spread at the Göksu delta developed in the center of the Silifke city located in the eastern-southeastern part of the study area.
