Magnitude 7 earthquake (February 5, 1663) affecting New France (now Quebec, Canada)
One of the largest earthquakes in Canadian history, it struck New France in 1663 with an estimated magnitude between 7.3 and 7.9, affecting much of eastern North America.
Key Facts
- Date
- February 5, 1663
- Moment Magnitude
- 7.3 to 7.9
- Time of Occurrence
- 5:30 p.m. local time
- Max Mercalli Intensity
- X (Extreme)
- Primary Hazard
- Landslides and underwater sediment slumps
- Affected Area
- Large portion of eastern North America
By the Numbers
Location
Cause → Event → Consequence
The earthquake originated along a seismically active zone near the Saint Lawrence River, with the epicentre located between the mouth of the Malbaie River to the north and the mouth of the Ouelle River to the south, in the region of the Saguenay Graben, a known geological fault system in what is now Quebec, Canada.
On February 5, 1663, at 5:30 p.m. local time, a major earthquake with a moment magnitude estimated between 7.3 and 7.9 struck New France. It reached a maximum perceived intensity of X (Extreme) on the Mercalli scale, shaking a large portion of eastern North America and causing widespread landslides and underwater sediment slumps in the St. Lawrence estuary region.
The earthquake triggered extensive landslides and underwater sediment failures near the epicentral region. Because European settlement was sparse at the time, first-hand accounts were largely preserved by Catholic missionaries, whose records later became critical sources for historians and seismologists attempting to reconstruct the event's magnitude and damage scale.