Abstract: Based on the data of suspended load in Glacier No.72 runoff at Qingbingtan in the Tomor Peak region, measured in August 2008, in this paper the mathematical statistical method is used to find out the particle size properties of suspended load in glacier runoff. The results show that the suspended load was dominated by fine materials, there was a high fluctuation in the contents of grain-size components of suspended load, the proportions of particles <63 μm, >63 μm and <4 μm were 68%, 32 % and 1.34 % of the total suspended load respectively, and their distribution curves were bimodal. There were different relationships between silt content and grain size of suspended load. With an increase of silt content, sand-sized material increased, but silt-sized and clay-sized materials decreased. There was no significant relationship between particle size parameters and discharge. Such weak correlation reveals that the suspended load of glacier runoff is mainly affected by the sand-silt source regime, ice-snow melt water can increase sand-sized material, and precipitation events can increase the silt-sized material.

Key words: glacier runoff, suspended load, particle size composition, Glacier No.72, Tomor Peak