Glacial earthquakes under Antarctic ice stream

timesofindia.indiatimes.com...

WASHINGTON: Seismologists have found seismic signals from a giant river of ice in Antarctica, each one equivalent to a magnitude of seven earthquakes.

The signals have been found by Douglas A. Wiens from Washington University, and colleagues at Pennsylvania State University and Newcastle University in the United Kingdom.

They combined seismological and global positioning system (GPS) analyses to reveal the two bursts of seismic waves from an ice stream in Antarctica every day, each one equivalent to a magnitude seven earthquake.

The ice stream is essentially a giant glacier 60 miles wide and one-half mile thick.

The data shows that the river of ice moves about 18 inches within ten minutes, remains still for 12 hours, then moves another eighteen inches. Each time it moves, it gives off seismic waves that are recorded at seismographs all around Antarctica, and even as far away as Australia.

Seismic waves from what are loosely called "glacial earthquakes" mainly near Greenland were originally reported in 2003, and the numbers have been increasing in recent years.....more..





- That must be one heck of a sound when that stream slips that 18 inches.. but it's not great news that this is happening all the time now.

kind of makes the issue of "what is causing" GW kind of moot in my opinion.
nice post.

Yeah, i have to agree.... we spend way too much time arguing about the cause, but we should be trying to do something about the effect..

the ocean comes up even a meter, theres alot of us in trouble..... this just goes to show how fast we will be in it.

a bit of a side note... I live in Vancouver, bc.... and yes, much like alot of people we have been having a colder year.. it's normal la nina..
I have been doing some research and if you want warm.. go above the arctic circle or alaska...
whitehorse, yk has been 5 - 10 degrees warmer than us for some time now... with it being that warm above the arctic circle, it can't mean good things.

Perhaps this is just the beginnings of the polar shift that the planet will be going through. I live in Vancouver too and yes it is colder than usual. I was hoping with the polar shift our climate would become more like Mexico's but its looking more likely that we'll be the next Arctic. We've also had record snow falls for the last 2 years. up to and over 10 feet on some of the local mountains.

I have mentioned a few times already but not many have realised there is alot of volcanic activity under the ice at the moment. It would explain this and alot of the glaciers breaking apart aas we have seen alot of lately.

This ice dropping into the sea effects the weather globaly and there we have it. Climate change.

Here is pne example Volcano Live