MercoPress, en Español

Montevideo, September 21st 2024 - 12:07 UTC

 

 

Chile's massive 2010 earthquake caused Antarctica glaciers to calve and 'icequakes'

Wednesday, August 13th 2014 - 01:15 UTC
Full article 3 comments
 Scientists found that almost 30% of the stations revealed definitive proof of high-frequency seismic signals as the surface-wave reached Antarctica. Scientists found that almost 30% of the stations revealed definitive proof of high-frequency seismic signals as the surface-wave reached Antarctica.
“We interpret these events as small icequakes, most of which were triggered during or immediately after the Chilean main shock” said Zhigang Peng “We interpret these events as small icequakes, most of which were triggered during or immediately after the Chilean main shock” said Zhigang Peng

A massive earthquake that struck Chile in 2010 caused glaciers thousands of miles away in Antarctica to calve, a study published Sunday in the journal Nature Geoscience found. Seismic surface waves radiating away from the earthquake’s epicenter traveled some 4,700 kilometers before passing through Antarctica’s ice sheets and causing small tremors, or “icequakes.”

 The researchers examined seismic data from dozens of stations in the hours before and after the March 2010 Chilean earthquake. They eliminated the longer-period signals as the seismic waves moved from the faraway epicenter to determine high-frequency signals from close-by sources. They found that almost 30% of the stations revealed definitive proof of high-frequency seismic signals as the surface-wave reached Antarctica.

“We interpret these events as small icequakes, most of which were triggered during or immediately after the passing of long-period Rayleigh waves generated from the Chilean main shock,” explained study leader Zhigang Peng, an associate professor in the School of Earth and Atmospheric Sciences.

“This is somewhat different from the micro-earthquakes and tremor caused by both Love and Rayleigh-type surface waves that traditionally occurs in other tectonically active regions thousands of miles from large earthquakes.”

Interestingly, the newly discovered icequakes react only to volumetric deformation from far-off seismic events.

“Such differences may be subtle, but they tell us that the mechanism of these triggered icequakes and small earthquakes are different,” Peng noted. “One is more like cracking, while the other is like a shear slip event. It’s similar to two hands passing each other.”

According to the researchers, the icequakes took place in different regions of Antarctica. Some were rapid bursts, lasting less than a second, and others lasted up to 10 seconds.

The researchers contend that the source locations of the icequakes, while hard to identify because of limited seismic network coverage on the continent, are likely formed extremely close to the ice surface.

Categories: Environment, Antarctica, Chile.

Top Comments

Disclaimer & comment rules
  • ChrisR

    Oh dear, so the “global warming”, sorry, “climate change” did NOT cause all the Antarctic ice problems after all. It was the massive Chilean ‘quakes in 2010 that caused the damage.

    Couple that with the known “warm currents” coming upwards from the depths of the shallow sea to the ice, further exacerbated the 'problem' of raising the sea levels world-wide by 200 meters, oh, sorry, TEN MILLIMETRES, then what can we conclude?

    1) The Earth has ALWAYS HAD CLIMATE CHANGE! This is well known to science and is proven by actual FACTS.

    2) There are THREE THOUSANDS SCIENTISTS with a consensus that this is going to happen. Consensus is opinion and lacks scientific proof. NASA is on the bandwagon, not to prove anything but to suck up to the US government and anybody else that will give them money for what they really believe in: SPACE.

    There are millions of well qualified actual scientists on this planet. Where are they in all this hysteria? Looking at the laughingly called evidence and deciding whether there is any TRUTH in these claims before they produce their work, BASED ON SCIENCE.

    3) The biggest threat to mankind comes from nature itself. The AIDs disaster has killed more than 20 million and is still killing people. Now we have Ebola, another disaster out of Africa. If we are really lucky perhaps 2 or 3 Bn from the 6 Bn may live? Perhaps much less.

    The WHO requires the dead to be BURNT, not buried. The latest Ebola strain is a tough little bugger it seems and needs burning to ensure clean ground. Once it’s off and running in a community they are in for a nightmare experience: anybody been on a plane lately?

    So two questions:

    Can YOU burn two people by yourself, because that is what it may come to?

    And what about global warming when 4 Bn people are burnt? If the fires are not hot enough in temperature they allow all sorts of particulates and nasty chemical compounds to be sent aloft, only to come down again.

    Have a think about that.

    Aug 13th, 2014 - 10:48 pm 0
  • The Chilean perspective

    1 ChrisR.
    The biggest threat to mankind comes from us.

    Aug 14th, 2014 - 10:26 am 0
  • ChrisR

    @ 2 The Chilean perspective
    “The biggest threat to mankind comes from us.”

    Yes, and are we not part of 'nature', I know I am?

    I sometimes which I could exchange body parts like replacing the brakes on a car but alas no.

    Ebola and the way it can be carried around the planet is a far greater risk to those living on the planet than ever the climate change crap is. It will kill you now.

    As an engineer and scientist I keep asking 'please show me the scientific evidence: the numbers and where they come from for global warming / climate change / whatever next they name it when it doesn't match the reality anymore'. That's all.

    Trouble is, they can't do it.

    Aug 14th, 2014 - 05:55 pm 0
Read all comments

Commenting for this story is now closed.
If you have a Facebook account, become a fan and comment on our Facebook Page!