Postglacial rebound and the focal mechanisms of eastern Canadian earthquakes

A detailed numerical model of postglacial rebound for the eastern Canadian Arctic is described with special attention being paid to Baffin Island. This numerical model is able to account for the observed uplift patterns as recorded by the relative sea-level histories of discrete sites distributed throughout the study area. These uplift patterns show regional trends, so the same model can be used to interpolate between data sites and to estimate the uplift history at any arbitrary site within the study area.By treating the lithosphere as a thin elastic plate, spatial variations in the uplift pattern can be translated into estimates of lithospheric stress. The model predicts the variations in uplift as a function of both space and time since deglaciation and can therefore be used to estimate the temporal evolution of lithospheric stress following deglaciation.The stress so calculated is treated as a perturbation to an ambient stress field having its origin in other processes. Postglacial rebound is shown to...