The mid-to-late Holocene water level and climate changes of Lake Salda (SW Anatolia/Turkey): Evidence from high-resolution seismic and sediment core records

Abstract

The sedimentary sequence in Lake Salda has been first documented in detail by analyses of high-resolution seismic profiles and sediment cores together with onshore outcrops along the present coastline of the lake. Such a multi-proxy approach provides a sensitive record of changing lake level and depositional conditions in Lake Salda during the mid-to-late Holocene. The low water level during the middle Holocene is followed by subsequent lake level decrease until 1690 cal year BP due to a drier climate. This prominent climate deterioration induced the coastal regression in the lake as inferred from the progradational deltaic sequences in the high-resolution seismic record. During the same period of a dry climate, oligotrophic lake conditions gave rise to the formation of stromatolite in the lake, timely coinciding with the Roman Warm Period. The following period of the late Holocene is represented by considerable lake level drop due to the enhanced dry climate that is earmarked by prominent erosional truncation surface and channel-incisions in the seismic profiles. This aridification phase is subsequently followed by transgressive lake level during 1690-1050 cal year BP, giving rise to a retreat of the deltaic deposit further inland as documented in the high-resolution seismic profile. The further deepening of the lake by contributions of both climate and tectonics during the last 650 cal year BP produced a transgressive unit with typical of onlapping architecture in the seismic reflection profiles and the formation of Gilbert-type fan deltas along the shoreline.