Accession Number : AD0710843

Title :   ICE-FABRIC STUDY OF THE MAWSON REGION, EAST ANTARCTICA,

Corporate Author : DEPARTMENT OF SUPPLY MELBOURNE (AUSTRALIA) ANTARCTIC DIV

Personal Author(s) : Kizaki,K.

Report Date : 06 FEB 1968

Pagination or Media Count : 24

Abstract : Attempts are made to test the relation predicted by Brace (1960) between strain-rates and the ice-fabric patterns obtained at Mawson station, east Antarctica. These orientation fabrics not only are hardly related to the prediction by Brace (1960) or Kamb (1959) but also change easily within a strain grid with 100 m diagonals. Stable patterns of two- and three-maximum fabrics are confirmed. The latter is common and stable in the coarse ice at the surface of the ice sheet. It is apparent that the fabric patterns are generally related to the grain-size. The single-maximum fabric always occurs in fine-grained ice, then more maxima are formed in the course of grain growth. It appears that syntectonic-secondary recrystallization is effective in producing the orientation fabrics with two, three and multiple maxima. Also, the maxima always shift away from the pole of foliation as grain-size increases and there are several stable positions of maximum such as 0, 17, 23, and 30 degrees. It is expected that further stable angles would occur with coarser crystals as found in temperate glaciers. (Author)

Descriptors :   (*GLACIERS, STRUCTURAL PROPERTIES), (*ICE, ANTARCTIC REGIONS), STRAIN(MECHANICS), CRYSTAL STRUCTURE, PARTICLE SIZE, SURFACE PROPERTIES, AUSTRALIA

Subject Categories : Snow, Ice and Permafrost

Distribution Statement : APPROVED FOR PUBLIC RELEASE