The Upper Marine Limit in the Little Whale River Area, New Quebec

• Published in: ARCTIC
• Main Author: Archer, David R.
• Format: Article in Journal/Newspaper
• Language: English
• Published: The Arctic Institute of North America 1968
• Subjects: Glaciation; Sea level; Hudson Bay; James Bay; Hudson; Baleine; la Baleine; La Petite Rivière; Petite rivière de la Baleine; Arctic
• Online Access: https://journalhosting.ucalgary.ca/index.php/arctic/article/view/66310

The relatively high land in places near the east coast of Hudson Bay in this area enables a more accurate estimate of direction and tilt of the upper marine limit plane to be made and thus to throw light on the emergence of this area after the last glaciation. The lower limit of perched boulders was used to indicate the height of the marine limit, for they represent the limit of wave action, whereas evidence given by the highest marine shells was inconclusive. The method of altimeter measurements and instrumental errors are stated. Analysis of data from 21 sites shows that the upper marine limit plane is tilted up toward 232 degrees ± 36 degrees(toward Hudson Bay); data from two points in the Richmond Bay area gave a tilt up toward 227 degrees ± 24 degrees. The varied isostatic readjustment indicates a major center of ice dispersal in the southern Hudson Bay/northern James Bay region during the Wisconsin glaciation. La limite supérieure de la transgression marine dans la région de la Petite rivière de la Baleine, Nouveau-Québec. À l'aide d'un altimètre, on a mesuré en 21 sites l'altitude de la limite supérieure de la transgression marine, indiquée par la limite inférieure des blocs perchés. L'analyse de ces cotes d'altitude indique que le plan de la limite supérieure est relevé vers 232º ± 36º. En ajoutant deux mesures géodésiques obtenues par Stanley en 1939, on arrive à un relèvement dirigé vers 277º ± 24º. On peut croire que ce rajustement isostatique variable indique la présence d'un centre majeur de dispersion glaciaire wisconsinienne au voisinage du sud de la mer d'Hudson et du nord de la baie de James.