1663 Charlevoix earthquake

1663 Charlevoix earthquake

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USGS-ANSS	ComCat
Local date	February 5, 1663 (1663-02-05)
Local time	17:30
Magnitude	7.3–7.9 Mw
Epicenter	47°36′N 70°06′W / 47.6°N 70.1°W / 47.6; -70.1
Areas affected	New France British America
Max. intensity	MMI X (Extreme)[1]

The 1663 Charlevoix earthquake occurred on February 5 in New France (now the Canadian province of Quebec), and was assessed to have a moment magnitude of between 7.3 and 7.9.^[2] The earthquake occurred at 5:30 p.m. local time and was estimated to have a maximum perceived intensity of X (Extreme) on the Mercalli intensity scale. The main shock epicentre is suggested to have occurred along the Saint Lawrence River,^[3] between the mouth of the Malbaie River on the north and the mouth of the Ouelle River on the south. A large portion of eastern North America felt the effects.^[3] Landslides and underwater sediment slumps were a primary characteristic of the event with much of the destruction occurring near the epicentral region of the St. Lawrence estuary and also in the area of the Saguenay Graben.

The event occurred during the early European settlement of North America and some of the best recorded first hand accounts were from Catholic missionaries that were working in the area. These records were scrutinized to help determine the scale of damage and estimate the magnitude of the quake in the absence of abundant records from that time period.^[4]