Late Quaternary landscape evolution of the southern Marmara region: paleogeographic implications for settlements, NW Turkey

Abstract

This study presents the late Quaternary evolution of the southern Marmara region in northwestern Turkey and discusses the suitability of the area for settlements. It is based on interpretation of sediment analyses together with radiometric dates obtained from drilling cores. As three-fourths of the southern Marmara region (ca. 30,000 km(2)) is covered by the Susurluk Drainage Basin (SDB), the study focuses on this basin. The SDB has a concave surface morphology dipping northward, with highlands in the south (ca. 1300-1700 m a.s.l.) and lowlands in the north (ca. 0-250 a.s.l.). Lake Manyas, Lake Ulubat, and south-north flowing rivers, together with deep gorges and large valleys, are basic elements of the landscape. Quaternary deposits are largely confined to the late Pleistocene and Holocene time interval. Results suggest that, as a whole, the Southern Marmara region has been subjected to intense erosion up to the Late Pleistocene. During the Late Pleistocene and Holocene, depositional dynamics and channel migrations are recorded in river valleys, where sediments evidence occurrences of flooding and backswamps. Landscape analyses show that the SDB was not attractive for human settlements in the Late Holocene, with the exception of the Daskyleion and Appolonia sites, in opposition to other parts of western Anatolia, which have been densely occupied since the Chalcolithic Age. According to our results, the location of Daskyleion on a hill near Lake Manyas was likely chosen for security reasons. Lake water and large permanently wet areas (swamps) may have indeed provided a natural contribution to the defense of this Phrygian town.