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Our study demonstrates the importance of detailed lithostratigraphic and biostratigraphic analyses of deposits of lake-side terraces and alluvial fans in attempts to identify fluctuations of climate characteristics such as precipitation and evaporation rates, and of local conditions for water balance changes in the central part of Turkey during the last 20,000 years. Lake Tuz basin, central part of the Anatolian Plateau, Turkey, had two high lake-level stages dated as about 20,000 - 17,000 years ago and about 13,000 years ago. At the high lake stages, water level rose more than 15 m higher than the present lake level, and the lake area spread widely to near the southern edge of the basin, as inferred by lithologic and chronological investigation of drilling cores. In the Holocene, lake level fell and the southeast part of the basin became extensive lake terraces. Alluvial fans have formed along the edge of the upland area on the terraces in the Holocene. Stratigraphy and dating of the fan deposits show the fluctuations in the depositional rates of the fans. Major formative stages of the fans are dated about 7000-5500 and 2500-2000 years BP, and several times of minor stages (probably 4300 and 3000 years BP) occurred between the two major stages. Our archaeological research shows that there are strong relationships between the distributions of archaeological sites of this area and the above geo-environmental histories. (C) 2002 Elsevier Science B.V All rights reserved.