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• CN 62-1072/P
• ISSN 1000-0240
• 创刊于1979年
• 主管单位：中国科学院
• 主办单位：中国科学院寒区旱区
•                  环境与工程研究所
•                  中国地理学会

• 研究论文 •

### 天山乌鲁木齐河源1号冰川表面应变率的初步研究

1. 中国科学院兰州冰川冻土研究所
• 收稿日期:1984-10-11 出版日期:1986-02-25 发布日期:2012-04-26

### Preliminary Study on Strain-Rate on Surface of Glacier No.1 at the Headwater of Urumqi River, Tianshan

Han Jiankang, Chen Xiaomei, Sun Zuozhe

1. Lanzhou Institute of Glaciology and Geocryology, Academia Sinica
• Received:1984-10-11 Online:1986-02-25 Published:2012-04-26

Abstract: Based on theory of plasticity, the authors have analyzed Glacier No.1 for its strain-rate distribution on the surface and the relation of crevasse pattern to strain-rate distribution. Following conclusions have been reached1) The distribution of strain-rate on glacier surface is under the direct control of ice mass conditions, such as ice thickness and slope of the surface, as well as the shape of channel and the pattern of ice movement (extending flow or compressing flow). Crevasses, the reaction of ice to strain-rates, are remarkable signs. The areal strain-rates on the surface represent variation in strain-rate gradient in a relative wider range.2) The marginal shear strain-rates play a prominent role on the profile where longitudinal strain-rates are smaller. This explains why crevasses develop more strongly near the margin area of a glacier.3) Generally speaking, crevasses form when the greatest principal extending strain-rate exceeds 0.01 a-1 on Glacier No.l. It was found smaller than 0.03 a-1 on Blue Glacier in U. S. A..4) The distribution of strain-rate on glacier surface is a result of integration of many factors. Thus, it is unreasonable to divide glacier surface into extending strain-rate region and compressing strain-rate region by snow-line only.5) The shape of the channel above all its curvature, has great effect on the distribution of strain-rate. Usually, where there is greater curvature in the channel, higher compressing strain-rates occur on the concave side, while OH the convex side, higher extending strain-rutes form. This is commonly rtue for all valley glaciers.