Do Earthquakes Trigger More Earthquakes?
12 January 2010. 7.0 magnitude earthquake strikes just outside of Port-au-Prince, Haiti. 230,000 people die, 300,000 injured, 1,000,000 made homeless, 250,000 residences and 30,000 commercial buildings destroyed.
Could these quakes be related? Does one Earthquake directly cause others to happen in different parts of the planet?
Ross Stein at the U.S. Geological Survey states. “The interesting thing is, any earthquake of let’s say magnitude six or larger, sends out its ripple of seismic waves, just like throwing a stone into a pond. And for a magnitude six or larger, those waves encircle the entire globe. And every single sand grain on the planet is dancing to that music.”
NPR asked this same question in October last year, after a series of quakes. They reported:
In Samoa, more than 100 people died after a magnitude 8 quake triggered a tsunami on Tuesday. Less than a day later, a magnitude 7.6 earthquake caused more than 400 deaths and widespread damage in Indonesia. A third earthquake struck in Peru, magnitude 5.9, on Wednesday.
According to Don Blakeman, a geophysicist with the USGS, “It’s coincidental. These quakes are not connected. We constantly have quakes going off. It takes one big damaging earthquake to get people’s attention and then they start noticing all the quakes.”
Kuo Kai-wen, director of the Seismology Center of Taiwan’s Central Weather Bureau concurs. “the Taiwan, Chile, and Haiti quakes involved different tectonic plates. Globally, he says, there’s an average of one magnitude 8 or higher earthquake per year, some 17 magnitude 7 or higher quakes, and 170 to 180 of magnitude 6 or larger.”
He adds, “Because Haiti just happened, everyone’s paying more attention to earthquakes.”
In Haiti, by 24 January, there were a minimum of 52 additional aftershocks measuring 4.5 or greater. According to NPR, there have been over 200 tremors over 5.0 on the Richter Scale that followed the massive 8.8 that struck off the coast of Chile on in the same fault zone. More aftershocks are expected in Taiwan. However, aftershocks are quite normal according to seismologists, and this doesn’t mean that strong shocks in one part of the world can trigger more in other parts.
Dr. Tom Parsons, a Seismologist with the US Geological Survey clarified the correlation of strong Earthquakes to their aftershocks: “Of course, in the Sumatra area is very active at the moment because of the giant earthquake that happened there back in 2004. So if you were going to blame this most recent event [from October 2009] on anything, I’d probably look at that big magnitude nine event that happened then as the root cause, more than the Samoa event.”
Thus, the world’s scientific experts tend to be in agreement that despite local aftershocks, there is no direct causation between large earthquakes in different parts of the world.
Editor’s Note: Please follow The News Junkie Post on Twitter.