Press Release of the 1925 Charlevoix-Kamouraska earthquake

On February 28, 1925, The Charlevoix-Kamouraska Region Shook All of North-Eastern North America

"In some buildings there was such a swaying motion that chandeliers rattled and dishes were moved. The effect was like the heaving of a ship at sea." (Quebec Chronicle, 1925)

On February 28, 1925, one of the most powerful earthquakes of the 20th century rocked the lives of thousands of people -- an earthquake measuring 6.2 on the moment magnitude scale occurred in the Charlevoix-Kamouraska area. The shock was so strong that the earthquake was felt more than 1,000 kilometres from the epicentre. In the weeks that followed, dozens of aftershocks continued to shake the area and helped keep its inhabitants living in fear.

This earthquake caused considerable damage near the epicentre along the St. Lawrence River. The cracked walls, fallen chimneys and broken windows changed the view that people had of this region, which has since been called, in the language of seismologists, the Seismic Zone of Charlevoix-Kamouraska. In addition to homes, some very important structures were damaged by the quake: Manoir Cabot near La Malbaie, the Gare du Palais in Québec (a railway terminal) and several churches as far away as Shawinigan. But, for more than its material damage, this earthquake became deeply etched into the minds of an entire generation.

This seismic area is still the most active in eastern Canada. Five major earthquakes measuring 6 or greater have occurred in the region: an earthquake with a magnitude of 7 in 1663, two quakes measuring 6 in 1791 and 1860, another of 6.5 in 1870, and this 6.2 in 1925. The first earthquake to be recorded was that of 1925; the others were estimated based on historical information.

From 1978 - when a seismographic network of seven local stations was put into place - to 1999, some 2,500 earthquakes were recorded, 54 of which were of a magnitude greater than 3 and 8 registering 4 or greater. This represents an average of 250 quakes per year, with approximately five strong enough to be felt by the population (magnitudes measuring greater than 2.5).

Scientists . . .

At the Geological Survey of Canada (GSC), a division of Natural Resources Canada, seismologists study earthquakes and try to understand them better. Their work consists of recording and analysing earthquake data. They then delineate the areas that are most susceptible to earthquakes and determine values of ground movement that are then prescribed in the National Building Code. As a result, the seismologists help engineers build safer and more resistant buildings in areas of higher earthquake risk.

"In addition to interpreting earthquakes, our group informs and advises emergency organizations, the media, engineering companies, electricity companies and the public on different aspects relating to earthquakes. We also participate in improving emergency procedures for earthquakes, especially with regard to public communications," said Maurice Lamontagne, research seismologist at the GSC.

How do we deal with this type of event?

Earthquakes can occur at any time and anywhere in Canada. Even though it is impossible to predict earthquakes, here or elsewhere in the world, historical reports and more recent data clearly indicate that this region is subject to significant earthquakes. The best way to face this phenomenon is to prepare for it.

Before an earthquake occurs, it is essential that you and your family draft an emergency plan. First, you must evaluate the potential sources of danger inside your house, especially objects that can fall and cause injuries. Prepare an emergency kit that contains the basic needs for your survival, such as water, warm clothing, a battery-operated radio and a flashlight. During an earthquake, you must protect yourself from objects that can fall and cause injuries. If you are at home, take cover under a table or any other solid piece of furniture -- get away from windows, bookcases and mirrors. If you are outside, stay far away from buildings and electrical wires. After an earthquake, evaluate the damage, and, most importantly, don't be foolhardy. If a situation seems dangerous, stay calm and wait for help. By speaking about the event calmly and just as calmly considering the possibility of aftershocks, you can reduce your own anxiety and that of your family members.

Thanks to good information, sensible advice and solid preparation, you and your family will be ready to face such a situation.

For more information . . .

You can find a lot of information as well as practical advice on the Natural Resources Canada site at EarthquakesCanada.

This site also contains a special section on the 1925 earthquake, including descriptions and photographs of damage. To continue studying earthquakes and evaluating their impact, GSC seismologists have devised an earthquake survey. If you have felt the Earth move under your feet, share your comments and data with them using their Web site or by telephone at (613) 995-5548. In this way, you can add to the existing information, whether about a recent earthquake or the one in 1925.