Guxiang and Baiyu Glaciations are two previously recognized local glaciations of the Tibetan Plateau. They have been widely used as the reference standard for classifying Late Quaternary glaciations on the Tibetan Plateau and its surrounding mountains. However, the numerical chronologies of both glaciations have been lacking. In this study, cosmogenic 10Be dating was undertaken to define the timing of these two glaciations. The surface boulders deposited by the glaciers of the Guxiang and Baiyu Glaciations have exposure ages of 112.9±16.7–136.5±15.8 ka BP and 11.1±1.9–18.5±2.2 ka BP, respectively. It is likely that the Guxiang and Baiyu Glaciations correspond to marine isotope stages 6 and 2, respectively.
1 November 2002 in Science in China Series D: Earth Sciences
We present a glacial geomorphological map (1:825,000) of the Parlung Zangbo Valley in the southeastern Tibetan Plateau based on Google Earth imagery and the 30 m ASTER Global Digital Elevation Model (ASTER GDEM). The mapped region covers 2.9 × 104 km2, including abundant glacial landforms such as glacial valleys, marginal moraines (including terminal moraines and lateral moraines), and hummocky moraines. Glacial valleys are distributed mainly above 2100 m a.s.l. with lengths from 1 to 130 km. Multiple marginal moraines occur along the glacial valleys, indicating the presence of multiple glacial events. The lowest moraines are distributed mainly at the mouth of each valley between 2400 and 4000 m a.s.l. Hummocky moraines are mainly distributed in the two main tributary valleys: the Bodui Zangbo Valley and the Yigong Zangbo Valley. One ice-dammed paleolake was mapped with a surface area of 12.5 km2. The mapped glacial features (including contemporary glaciers) cover 1.2 × 104 km2, about 40% of the mapped area, representing the minimum extent of maximum glaciation. This map provides a useful data set for reconstructing the timing and extent of paleoglaciations in this area.