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The author of this paper and other scientists have investigated this region for many years.Basing himself upon the first-hand data collected in the field work, he gives a comprehensiveand systematic discourse of the types of the periglacial 1andforms of the plateau, their distri-butions and conditions of development, and points out that such phenomena as rock-like icecap, rock glaciers, thaw slide masses, self-extrusive pingos and stratified scree of theplateau have their own peculiarities. Three types of periglacial topographical regions, i.e.maritime, subcontinental and continental are classified and their evolutionary models given.He proposes that different types of regions have their own vertical spectrum of periglaciallandforms, and the altitude of the periglacial phenomena varies with the ’longitudinal gra-dient value’. The existence of altitudinal periglacial zone in the Qinghai-Xizang Plateauis obvious1y controlled by the longitudinal zone. Finally, he proposes that no upper limit ofperiglacial process exists on the globe, but there do exist upper and lower periglacial zonesabove and below snowline and 0℃ isotherm in summer, i.e. ’quasi-symmetrical periglacialzone’.
The author of this paper for many years. Basing himself upon the first-hand data collected in the field work, he gives a comprehensive and systematic discourse of the types of the periglacial 1 and forms of the plateau, their distri- butions and conditions of development, and points out that such as rock-like icecap, rock glaciers, thaw slide masses, self-extrusive pingos and stratified scree of theplateau have their own peculiarities. Three types of periglacial topographical regions, iemaritime, subcontinental and continental are classified and their evolutionary models give. The existence of altitudinal periglacial zone in. the Qinghai-Xizang Plateauis obvious1y controlled by the longitudinal zone. Finally, he 意 that no upper li mit of periglacial process exists on the globe, but there do exist upper and lower periglacial zones above and below snowline and 0 ° is isotherm in summer, ie ’quasi-symmetrical periglacialzone’.