Late Glacial lake-level changes in the Lake Karakul basin (a closed glacierized-basin), eastern Pamirs, Tajikistan

摘要

The lake-level variations during the Late Glacial in the Lake Karakul basin (a closed glacierized-basin), in the northernmost part of the eastern Pamirs, were reconstructed using geomorphological and sedimentological evidence, with a chronology developed using luminescence ages from sand-sized quartz and K-feldspar in the lake sediments. Lake transgression started before similar to 19 ka, with the peak water level of similar to 35 m above the present elevation occurring at similar to 15 ka. This was synchronous with a significant advance of the glacier in the catchment. Stepwise lake regression, including a rapid lowering of the lake level (similar to 13 m at similar to 12 ka), persisted until at least similar to 10 ka. Lake transgression and localized glacier expansion from similar to 19 to similar to 15 ka likely correlate with the more regional Late Glacial glacier advances across the semi-arid western Himalayan-Tibetan orogen and the eastern Pamirs. The longer-term trend of this lake transgression was probably caused by colder and/or wetter climatic conditions, forcing a notable glacier advance. (C) 2014 University of Washington. Published by Elsevier Inc. All rights reserved.