Postglacial rebound in Arctic Canada: similarity and prediction of uplift curves

Abstract

Twenty-one uplift curves from Arctic Canada indicate a similar proportional response through time. The time/altitude relationship can thus be expressed as a per cent of uplift within a specific time period. A graph of the results is a smoothly decelerating curve. Uplift curves can be approximated by the formula: U = A(1 − it)/(1 − i) where U is uplift, t is time with 0.0 years being the moment of site deglaciation, i is a constant for Arctic Canada equal to 0.677, and A varies with time and amount of recorded uplift. Tables and a figure are presented so that uplift curves can be predicted on the basis of: (1) elevation of the marine limit; and (2) date of site deglaciation. A comparison between Arctic Canada, east Greenland, and Fennoscandia indicates that relaxation times for a comparable period (10 × 103 years) are 2.5, 1.7, and 3.0 × 103 years respectively. Velocities derived from uplift curves allow the amount of residual uplift to be calculated. A figure of 100 m is suggested for a sector of Hudson Bay.