Origine de la préconsolidation des argiles du Saguenay, Québec

Abstract

The clays of Eastern Canada, and in particular the Saint-Jean-Vianney clay in the Saguenay region, have often been described as clays with a preconsolidation due partly to cementation. In order to check this assumption, the geological history and the geomorphology of the Saguenay region have been analyzed. Further to the evidence of significant erosion, available geotechnical data in the form of variations of water content, undrained shear strength, and preconsolidation pressure have been analyzed to determine the elevation of the original ground surface in the hypothesis of a preconsolidation resulting from deposition and erosion. The results of this analysis are in good agreement with the geological and geomorphological data and they suggest that cementation has had a negligible effect on the preconsolidation of the Saguenay clays. A regional map of preconsolidation pressures is also presented. Keywords: clay, preconsolidation, geomorphology, erosion, shear strength. [Journal translation]