Identification of the Eolian Components in Zigetang Co Sediments from the Central Tibetan Plateau

It is widely recognized that grain-size distributions of the lacustrine sediment tend to be polymodal and consist of two or more components. However, there is still great uncertainly in explaining the genesis of grain-size components due to the inherent complexity of their polymodal distributions. In this study, the grain-size components of the core sediments of Zigetang-Co, central Tibetan Plateau, were partitioned using the log-normal distribution function method and the relationship between the identity of each component and the specific sedimentary environment was investigated. The data indicate that the core sediments of ZigetangCo contain five distinct unimodal grain-size distributions representing five grain-size components. These components are specified from fine to coarse modes as clay, fine silt, silt, fine to medium sand and coarse sand. The percentage contribution of most sand components is shown to be correlated with eolian activities, only small number is probably correlated with water depth changing.