Aeolian sediments of different type are covering large areas on the Tibetan Plateau, ranging from loess and loess-like sediments on the mountain slopes to large dune fields on the leeward side of several lakes. This study presents a reconstruction of aeolian sediment transport in the surroundings of Lake Donggi Cona on the north-eastern Tibetan Plateau.
Larger dunes can be found in the southern part of the catchment. The heterogeneous dune field stretches in WSW to ENE direction. The source area of the sand is mainly in the neighboring valleys which have been occupied by small lakes in former times. Dating results based on infrared stimulated luminescence (IRSL) indicate a beginning of the formation of these dunes in the late Pleistocene. First results show a stabilization phase during most of the Holocene followed by a reactivation of sand during the last millennia.
A different dune field is situated on an alluvial fan on the eastern side of the lake. These dunes are much smaller in size and are presently degrading. IRSL ages indicate a formation of these landforms during the last 2000 years. They are most probably related to a higher availability of sand in the catchment due to varying lake levels of the Donggi Cona. These dunes are presently eroded due to increased grazing pressure. The sands are relocated to the larger dune complex next to the fan. Loess and loess-like sediments are located on isolated hill tops and on slightly inclining slopes in the mountains. These sediments have been deposited during the late Pleistocene and the early Holocene. However, loess - like sediments have been covering a much larger area in former times. Silty sediment on the highest terrace in the catchment mainly consists of relocated loess material. The deposition of these sediments has been dated to the early Holocene, shortly after the end of the formation of the loess deposits in the mountains.