• 论文 •

### 喀喇昆仑公路沿线冰川的近期进退变化

1. 中国科学院兰州冰川冻土研究所
• 出版日期:1980-04-15 发布日期:1980-04-15

### RECENT VARIATIONS IN THE GLACIAL TERMINIALONG THE KARAKORUM HIGHWAY

Zhang Xiangsong

1. Lanzhou Institute of Glaciology and Cryopedology, Acodemia Sinica
• Online:1980-04-15 Published:1980-04-15

Abstract: Present glaciers along the Karakorum Highway way are located at 35-39 degreesnorth latitude and 74-76 degrees east longitude. There’s a marked difference ekis-ting in the dominating features of the glasiers in the western section of Kunlun Shan(Muztagata Shan Kongur Shan), western section of the Karakoram (Hunza Kara-koram and Saltoro Karakoram) and western seetion of the Himalayas (Mt. NangaParbat). Results obtained through researches on glaciology indieate decidedly thatthe properties of glaciers and their active capability mainly depend on the level ofmass balance and that morphological types of glaciers depend on the topography ofpreglacial age and stages of development of glaciation.On the basis of repeated measurements at a fixed station, geomorphological in-vestigation and aeronautical observation and in the light of the documentary recordsand recalls of the local residents, we come to the conclusion that the termini alongthe Karakorum Highway have been subject to many fluctuations with in compara-tively recent times. From the eighties of the last century to the twenties or thirtiesof this century the glaciers either advanced in general or were relatively stationary.From the thirties to the sixties, the glaciers retreated on a wide scale. Since thesixties the changes in the positions of the glacier fronts have presented a very hetero-geneous picture. Take the glaciers in the western section of the Karakoram Moun-tains for instance. In this period a great number of them have been advancing, withsome of them retreating.In accordance to the amplitudes of glacial variations, the glaciers along theKarakorum Highway can be classified into two magnitudes.First the amplitude of several metres or several decades of metres during someyears or several decades of years. These include for instance, the glaciers in Mt. Muz-tagata Shan and Mt. Kongur Shan, which are characteristic of the continental typeglaciers.Second, the amplitude of some hundred metres during several years or decadesof years. The valley glaciers in the wetern section of the Karakoram Mountains andMt. Nanga Parbat belong to this category. They are normal glaciers with highlevel of mass balance and aetive motion.In addition, the amplitude of several kilometres during some years or severaldecades of years, such as Hasanabad Glaciers, Minapin Glacier and some others in theBasin of the Hunza River, which are the cyclic fast advancing glaciers of the surg-ing type.The surging glaciers in the basin of the Hunza River, their periodicity is byfar longer than that of the same types of glaciers in other parts of the world(usually 20-30 years). The superglacial topography of the surging glaciers in thebasin of the Hunza River is short of the folded moraines, a phenomenon resultedfrom the loops and folds in medial moraines, with the exception of the highly crevassedand at times great transverse cracks.We also discovered that the general tendency of the fluctuations of the glaciersalong the Karakorum IIighway seemed to bear a certain similarity to the fluctuationsof the existing Alpine glaciers in Europe, with the exception that the time lags alittle behind.The common characteristics of the termini of the advancing glaciers along theKarakorum Highway are as follows:The ice cliffs at the snout are steep and giant with their gradients exceeding30° and relative height over 80 metres. The front of ice cliff has a push moraineformed as a result of the pushing of the advancing glaciers and there are a lot ofrounded pubbles in the push moraines.