Abstract:

14 shallow snow / firn cores were taken by drilling with the PICO lightweight hand coring auger on Law Dome and Wilkes Land along a line approximately 111 °E longitude between 66°S and 74°S latitude. 5 of these cores, BJ, LJ24, GC30, GC40 and GC46, 20-30 m deep, are studied in detail in this paper. The densities of snow / firn were measured in a cold room at temperature between -18℃ and-14℃ by taking consecutive core samples and weighing the mass of each sample whose volume was known. The characteristics of the initial densification (till a density of 550 kg / m3) including the variation of snow / firn density with increasing depth, densification rate of snow / firn and the com-pactive viscosity coefficient of snow / firn are studied, and the factors affecting this initial densification process are discussed. From the obtained measurements, a relationship between compactive viscosity coefficient of snow / firn and mean annual temperature is found in case ρ=550 kg / m3 . For snow / firm on Wilkes Land, the relationship we found at a mean annual temperature below -25℃ (i.e. no melting features are present in stratigraphy) is very similar to that found by Nishimura and others (1983) on Mizuho Plateau, Antarctica.

Key words: Wilkes Land, snow, firn, densification