Accession Number : AD0682723

Title :   BUBBLE COALESCENCE IN ICE AS A TOOL FOR THE STUDY OF ITS DEFORMATION HISTORY.

Descriptive Note : Research rept.,

Corporate Author : COLD REGIONS RESEARCH AND ENGINEERING LAB HANOVER N H

Personal Author(s) : Weertman,Johannes

Report Date : SEP 1968

Pagination or Media Count : 13

Abstract : An analysis is made of the rate of bubble coalescence in a deforming ice mass. A total strain of at least 8 is required before appreciable coalescence occurs. The analysis has been applied to deforming ice shelves and ice sheets. No appreciable coalescence is expected in ice shelves but coalescence should occur in ice sheets (or glaciers) if the shear strain rate at the bottom surface is of the order of 0.075/yr or larger. Measurements of bubble concentration are capable of setting limits on paleo-strain rates of the present ice sheets. Bubble migration down temperature gradients presents complications to the study of bubble coalescence. (Author)

Descriptors :   (*ICE, CREEP), HISTORY, BUBBLES, GLACIERS, AIR, THICKNESS, STRAIN(MECHANICS), MATHEMATICAL ANALYSIS, THEORY, STRESSES, MEASUREMENT, DEFORMATION

Subject Categories : Snow, Ice and Permafrost
      Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE