Late Quaternary fluvial dynamics and landscape evolution at the lower Shulaveris Ghele River (southern Caucasus)

The southern Caucasus was intensively settled through the Neolithic period to present. Studies of late Quaternary fluvial dynamics and landscape development at the lower Shulaveris Ghele River in southeastern Georgia aid understanding of the Quaternary history of this region. Our studies show that following river aggradation to form a fan-shaped alluvial surface during the late Pleistocene, fluvial sedimentation shifted west, leaving a fan surface subject only to local fluvial and colluvial processes as well as late Neolithic settlement. At about 6 ka, the river avulsed to the east and eroded some late Neolithic settlements occupying the eastern portion of the fan. The avulsion was followed by 3 distinct episodes of aggradation at about 6 ka, 3-2 ka, and since 1.0 ka. No such aggradation is evident in the early Holocene. Regional Holocene fluvial activity in this area was apparently influenced by vegetation dynamics, possibly controlled by regional climatic and/or anthropogenic factors, and significantly differs from the eastern Mediterranean region. All late Neolithic settlements were originally built far from an active river, possibly indicating late Neolithic water management systems.