Massive earthquakes—such as the magnitude 9 quake that sparked the deadly Indian Ocean tsunami in 2004—can set off smaller tremors around the globe, a new study shows.
Traditional aftershocks occur close to the time of the original earthquake—often within days or a few weeks—as the earth adjusts to changes caused by the slippage along the original fault.
But smaller, more distant earthquakes can be triggered as low-frequency vibrations—somewhat like ocean swells—pass over faults. Such waves can't be felt by people standing on the ground.
It's too early to know if the recent deadly earthquake in China also triggered its own swarm of distant tremors, but "it wouldn't surprise me in the least," said study lead author Tom Parsons of the U.S. Geological Survey in Menlo Park, California.
(See photos of the China quake's aftermath.)
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China just had some after-shocks that left 71,000 more people homeless.
ReplyDeleteMakes you wonder if a component of HAARP is an earthquake weapon!
Weird stuff going on.
Heavy stuff Dad...G waves setting up a shock wave through synpathetic vibration? My nephew was telling me about HAARP and earthquakes a few years ago, but he believes in zero energy machines too. I'm beginning to think he's right again, (he has been on numerous occasions), but pretty sure that he can't get energy from nothing. He's got a bike wheel on his front porch that is covered with magnets that spins for a long time, but I'm pretty sure that friction and the conservation of energy and matter comes into play...G:
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