October 20, 1870 Tsunami: Cape Trinity, Quebec, Canada
A tsunami caused by an earthquake and a landslide began at Cape Trinity, Quebec, Canada on October 20, 1870. It killed 2 people, counting the earthquake or eruption that caused it.
Where the waves reached
The source of the tsunami. No runup with a place is recorded for it.
- Under 1 m
- 1 to 3 m
- 3 to 10 m
- 10 to 30 m
- 30 m and more
- Height not recorded
The tsunami
- Date
- October 20, 1870
- Source
- Cape Trinity, Quebec, Canada
- Cause
- Earthquake and landslide
- Earthquake
- The earthquake
- Runups recorded
- 0
- Waters
- Ocean
- How certain
- Questionable tsunami
- Source location
- 47.400° N, 70.500° W
The toll
- Deaths
- 2 with the earthquake or eruption that caused it
- Damage
- Limited (under about $1 million) with the earthquake or eruption that caused it
- Houses destroyed
- 16 with the earthquake or eruption that caused it
- Houses damaged
- Few (about 1 to 50) with the earthquake or eruption that caused it
Where the literature gives no number, NCEI records a description on a scale of 1 to 4, printed here in its words. Damage is in millions of US dollars of the year of the event, not adjusted for inflation.
What the record says
NCEI’s account, from the sources it cites.
There had been several instances of huge landslides occurring on the north shore of the St. Lawrence River and estuary in eastern Canada. Associated with these landslides, tsunamis occurred. Here two specific tsunamis (Feb. 5, 1663 and Oct. 20, 1870) were reconstructed based on the scanty information available. Examination has been made of some of the optical phenomenon that were described in connection with the occurrence of tsunamis. (reference #11927)
Assuming that it would take more than 200 years, our recent investigation of the cliffs surrounding the Cap Trinity in 2011 provide some hints as to where it may have taken place as shown in Figure 7. The area shown by the dashed line is the only one that would be close to what has been described above. We estimate that the maximum volume of this rockfall would be about 20 000 m3. We can see that there are many other scars left of rockfalls of unknown origin. This rockslide must have triggered a tsunami (Murty and Durvasula 1977) in a context illustrated in Figure 2d. (reference #11926)
More
Every tsunami in 1870The 1800sTsunamis of CanadaThe earthquakeThis day in weather historyAlerts in force
Sources
Tsunami events and runups from NOAA’s National Centers for Environmental Information, Global Historical Hazard Database, cited as NCEI/WDS, doi:10.7289/V5PN93H7. Public domain. Read 2026-09-24. NCEI tsunami event 5665.