DID A LARGE ICE SHEET REALLY OCCUR ON THE QINGHAI-XIZANG PLATEAU?
Zheng Benxing (Lanzhou Institute of Glaciology and Geocryology, Academia Sinica)
As early as the beginning of this century, there were divergent views on whether a large ice sheet covered the whole Qinghal-Xizang Plateau in the Quaternary glacial period. Hedin Sven (1899—1902), Luo Laixing et al. (1963), Cui Zhijiu (1964) and Zhen Benxing et al. (1976, 1979) considered that no large ice sheet formed on the Plateau. But E. Trinkler (1930) and V. M. Sinitsun (1958) belived that the whole Plateau was covered by a large ice sheet in the Quaternaty glacial period.Since 1981, M. Kuhle, a F. R. G. geomorphologist has several times argued with Chinese soientists that a large ice sheet existed on the Qinghai-Xizang Plateau, thus causing concerns about this problem in the circles of geoscience both at home and abroad. The main divergence of the two different views lies in the different understanding of the sediments, sedimentary sequences and landform on the plateau. Large amount of recent sediments and geomorpho-logical study show that most of the deposits regarded, as moraines and which were used to reconstruct very low paleosnowlines and extensive ice sheets are actually debris flow and slope wash-related deposits. Real glacial, deposits are not widespread on th Plateau and an extensive ice sheet did not develop.