Localization and magnitude of seismicity on February 5 1663 (Charlevoix) in landslide journals

The earthquake that occured on 5 February 1663 is the first strong historical earthquake recorded in Canada and is currently estimated to have been located near La Malbaie and to have had a magnitude M of about 7. It left various signatures in the landscape that reveal its extent and significance. In the terrestrial domain, landslides were observed in various regions of Quebec, including Betsiamites, Saguenay, Charlevoix, and Mauricie. In the subaqueous domain, related mass movements were found along the St. Lawrence Estuary, the Saguenay Fjord, and various lakes on the Canadian Shield and likely also in the Appalachian. The minimum cumulative volume of mass movements associated with the 1663 earthquake is 1.7 km(3). From the analysis of landslide-related data and using empirical methods for magnitude estimation, the position of the epicentre would be located in the Canadian Shield to the north of the St. Lawrence River with a minimum magnitude M of 7.2 +/- 0.2 and a maximum magnitude that would be close to the maximum for the Charlevoix area, which has been previously estimated at M = 7.8 +/- 0.6.