Middle to late Holocene sedimentation dynamics and paleoclimatic conditions in the Lake Ulaan basin, southern Mongolia

Abstract

This study presents a reconstruction of the middle to late Holocene sedimentation dynamics and paleoclimatic implications in Lake Ulaan, southern Mongolia for the first time. The dynamics is inferred from weathering intensity, Accelerator Mass Spectrophotometry (AMS) radiocarbon dating and estimated sedimentation rates. Result shows that a higher sedimentation rate of 4.6 cm.kyr‑¹ between 2.7 and 6.0 cal kyr BP and a lower sedimentation rate of 1.6-1.8 cm.kyr‑1 after 2.7-3.2 cal kyr BP are associated with a climatic shift from humid in the middle Holocene to arid in the late Holocene within the Lake Ulaan basin. This result from the Lake Ulaan basin in southern Mongolia correlates with the middle and late Holocene climatic records reconstructed from other lakes in Mongolia and Central Asia. Further investigation of lacustrine sedimentary sequences and more age data from Lake Ulaan are still needed to constrain better the Holocene sedimentation history in southern Mongolia and Central Asia.