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对滇西北海拔4 000~4 500 m山地的第四纪冰川发育和平衡线高度进行了研究.结果表明:古冰川发育主要依托海拔4 000~4 300 m的夷平面,早中期发育小型的冰帽以及流入四周谷地的山谷冰川,晚期主要发育规模较小的冰斗冰川.冰川主要发育期为末次冰期,古冰川平衡线、山体最高峰以及夷平面的高度显示,冰川发育所依托的夷平面在末次冰期时超过古平衡线,二者差值为50~400 m,为冰川发生提供了良好的地形与地势条件.冰川规模演化表明,滇西北地区多处山地MIS 3中期的冰川规模大于末次冰盛期(LGM),可能与MIS 3中期较强南亚季风带来较丰富的降水有关.古气候研究资料以及研究区的冰期系列表明,滇西北海拔4 000~4 500 m山地末次冰期的冰川作用是构造和气候相耦合的结果.
The development of Quaternary glaciers and the height of the balance line in the mountainous area of 4 000 ~ 4 500 m above sea level in northwestern Yunnan were studied.The results show that the development of ancient glaciers depends mainly on the flattened surface of 4 000 ~ 4 300 m above sea level, Cap, and valley glaciers that flow into the surrounding valleys, with the latter mainly developing glacial ice glaciers, the main developmental period of which is the last glacial period, the paleo-glacier balance line, the highest peak of the mountain and the level of the razor plateau, Over the paleo-balance line in the last glacial period, the difference between them is 50 ~ 400 m, providing good topography and topography for the occurrence of glaciers.The evolution of glacier scale shows that the glacial scale of MIS 3 in many mountains in the northwestern Yunnan is larger than the last The ice age (LGM) may be related to the more abundant precipitation in the stronger mid-South Asian monsoon during MIS 3. The palaeoclimate research data and the glacial series in the study area indicate that the glaciers of the last glacial period from 4 000 to 4 500 m above sea level in northwestern Yunnan The role is to construct a coupling with the climate.