A look at earthquakes across Central Alberta

A look at earthquakes across Central Alberta

Earthquakes are rare in this area, they are not unknown

On morning of Monday, March 4th, an earthquake estimated at 4.6 on the Richter scale hit.

It was centred west of Red Deer and south of Sylvan Lake. There was no reported physical damage, although power was out at Sylvan Lake for some time.

According to the extensive news coverage, this was the largest earthquake ever recorded in Central Alberta, at least in recent years.

Then, on Sunday, March 10th, a second earthquake, measuring 4.3 on the Richter scale, struck northwest of Rocky Mountain House. Again, there were no reports of damage, although many people reported that they felt it.

Quite naturally, these two incidents have caused a lot of comment, not only locally, but across the province. However, while earthquakes are rare in this area, they are not unknown.

Nevertheless, when they do occur, they are generally quite mild, in the 3 to 4 range.

On Saturday, August 9th, 2014, there was a 4.2 quake, again out by Rocky Mountain House. On March 9th, 2018, there was a 3.14 quake southwest of Red Deer and in 2017, there two 2.3 quakes east of Sylvan Lake.

The earliest report of an earthquake by Sylvan Lake occurred in early November 1904.

Newspaper accounts of the time stated that the quake was accompanied by a loud boom, much like a brief thunderstorm, that, “Travelled in a north westerly direction.”

There were no scientific measuring stations in those days so there is no record of how strong the quake was.

Moreover, the region was sparsely populated, which meant not that many people witnessed it. Nevertheless, the event only sparked curiosity, and not any fear or panic.

According to the late Les Hewson, there was a small quake that hit Red Deer during the 1930s during Fair Week. While the tremor was mild, he remembered that some brick chimneys cracked.

Earthquakes and tremors near Rocky Mountain House are less rare, particularly near Strachan, which is considered one of the relative “hot spots” of seismic activity in Alberta.

Usually, these quakes are three or less on the Richter scale. Instead of a noticeable bang, the disruption is about the same as a heavy truck driving past a house. Most often, the tremors are so mild that they are only recorded by seismic equipment and are not noticed by anyone.

Other parts of Canada are not so fortunate, particularly along the West Coast.

The biggest known earthquake occurred in January 1700.

Based on geological evidence, this was a very powerful quake. Some of the damage can still be clearly seen more than 300 years later.

In June 1946, a major earthquake, registering 7.3 on the Richter scale, occurred west of Courtney and Campbell River on Vancouver Island.

There was widespread property damage. There were two deaths attributable to the quake, one by drowning and the other by heart attack.

Canada’s largest recent earthquake (magnitude 8.1) occurred on August 22nd, 1949 near the Haida Gwaii (Queen Charlotte Islands). Again there was widespread property damage.

However, while this was a stronger quake than the one in 1946, because it was centered offshore, the damage was not as severe as the Vancouver Island earthquake.

The worst earthquake ever recorded in North America was the terrible Alaska Earthquake on Good Friday, March 27th, 1964. It registered 9.2 on the Richter scale, and 131 people lost their lives.

In Canada, more than $10 million in property damage was recorded as a result of tsunamis.

Also well remembered is the great San Francisco earthquake of April 18th, 1906. More than 3,000 people were killed and an estimated 80 per cent of the city was destroyed.

Among those who suffered heavy losses in the San Francisco quake were Fernand and Jeanne deJournel. They had lived in Red Deer in the early 1890s when Fernand managed a small general store business on Ross Street.

While they were here, one of their daughters died and was buried in the little cemetery that was located at Taylor Drive and 43rd St.

Fernand deJournel was one of those who joined the Klondike Gold Rush, but unlike most people, he made a fortune with a claim on Hunker Creek. He later built a lavish home in San Francisco. That home was destroyed in the earthquake. However, the deJournels were still very wealthy and were able to build a new mansion in the nearby community of Burlingame, California.