After a series of strong earthquakes were felt around the world this week, it has many people asking; Are earthquakes becoming more frequent?
The Weather Network spoke with Dr. Brent Ward, Earth Sciences Professor at Simon Fraser University in BC, to discuss the earthquake frequency and the potential for the "Big One" to hit Canada.
Q: After this week's series of quakes, would you say the earthquake frequency is increasing?
A: We don't think the earthquake frequency is increasing. Generally, for the larger earthquakes, meaning eight and greater, we expect one to two every year. But, in the past ten years we've had as many as four, but several years we've had none. What's probably happening is that many of these destructive earthquakes are happening in populated areas. And so, they're getting into the news and people are hearing about them. Whereas in most cases, some of these earthquakes happen in remote areas where there's very little damage and we don't hear about them.
Q: Was there a connection with all of the earthquakes that struck this week?
A: We don't think there's a connection between earthquakes that happen close to the same time in widely separated areas. There is the fact that if you get a large earthquake, you can get some fairly significant aftershocks in the same area, but generally, we don't feel that it extends out to other, different plates.
Q: After the large earthquake (magnitude 8.6) hit Indonesia on Wednesday, why was the tsunami impact far less significant than the deadly tsunami in Japan last March?
A: The previous earthquake that caused the tsunami that killed so many people, was an underthrust earthquake. We had one plate sliding under another causing movement such as this, which caused displacement of the water, which triggered the tsunami. So, in the case of the recent Indonesia quake, although it was a very large earthquake, the movement was side to side and so we didn't get that vertical movement of the sea floor. Therefore we didn't have a tsunami of the same magnitude.
Q: What is the likelihood of the "Big One" hitting here in Canada?
A: We can't forget the fact that here on the west coast, we're in a tectonically active area. We have a fairly high probability of getting an earthquake in the magnitude of 7.5 or so, and possibly even what we'd consider to be the "Big One," similar to what happened in Japan, and similar to what happened previously in Indonesia. So, it's just good for people to keep that in their mind, so that they have their earthquake kits ready, they have a family plan, a strategy to deal with a natural hazard that we really haven't had here since European settlement.