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Tremors Mean Antarctic Volcanism May Be Heating Up

Posted by timothy on from the slip-slidin'-away dept.

The L.A. Times reports on the discovery of seismic events (nearly 1400 tremors were recorded by researchers in 2010-2011) which seem to indicate the presence of volcanic activity 15 to 20 miles beneath the surface of western Antarctica. According to the article, "The area of activity lies close to the youngest in a chain of volcanoes that formed over several million years, and the characteristics and depth of the seismic events are consistent with those found in volcanic areas of Alaska’a Aleutian Islands, the Pacific Northwest, Hawaii and Mt. Pinatubo in the Philippines, the study concludes." Volcanism isn't a new discovery (Mt. Waesche, a volcanic mountain, is the believed origin of some ash mentioned in the article), but the newly detected seismic activity may be a harbinger for local melting from below of the Antarctic ice sheet, and possibly have long-term effects on the flow patterns of the overlying ice.

11 of 132 comments (clear)

  1. It will be ok. by mevets · · Score: 4, Funny

    We are getting rid of that ice as fast as we can.

    1. Re:It will be ok. by dbIII · · Score: 4, Insightful

      Can we please just discuss volcanoes instead of having a pissing contest over who is the biggest sociopath?

    2. Re:It will be ok. by The+Grim+Reefer · · Score: 5, Insightful

      To be somewhat blunt, I really don't care if part of NYC is under water as it is all over priced land owned by rich fat cats who can more than afford putting up a retaining wall or losing a piece of property.

      Have you ever been to NYC? Yes, there are some insanely rich people living there. There are also a hell of a lot more poor. Contrary to what you seem to think, the streets are not paved with gold. In fact, they are closer to the surface of the moon.

  2. Where's the link? by MatthiasF · · Score: 4, Informative

    Summary mentions an article from the LA Times.

    Here's the link:

    http://www.latimes.com/science/sciencenow/la-sci-sn-volcano-ice-antarctica-20131115,0,6645564.story

  3. Re:So what you're telling me by Alain+Williams · · Score: 5, Insightful

    I would not be surprised if the loss of the weight of the ice that has already melted is itself contributing to the emergence of the volcanoes. Less weight pressing down might make it easier for them to come to the surface.

    Disclaimer: I am not a geologist.

  4. Prepare not to be surprised by sam_vilain · · Score: 5, Informative

    There's a great book covering some of the science on this topic; reviewed here on NewScientist; very much worth the read. Actually what happens is that the crust "rebounds" in two phases. You can use the first phase to weigh the ice sheet as they are doing in Greenland. Then, the athenosphere (the molten layer, 15-150km deep which the crust/lithosphere sits atop) slowly slops in there and supplies extra heat and magma; generally quite a slow process, with some rebound from the last ice age still occurring.

    Upshot: it's certainly possible that the events are related.

    --

    1. Re:Prepare not to be surprised by ultranova · · Score: 4, Informative

      So a glass of water with ice cubes in it weighs more then a glass of water without ice?

      ...You do realize that Antarctica is a continent, not an ocean, right?

      Hmm.. do you know where I could get a scale precise enough to measure this effect on small scale so I can compare it with a larger glass of water called an Ocean?

      Nope, I guess you didn't.

      --

      Forget magic. Any technology distinguishable from divine power is insufficiently advanced.

  5. They're lying... by Type44Q · · Score: 5, Funny

    beneath the surface of western Antarctica

    They're lying: every part of Antarctica lies to the north.

    :p

    1. Re:They're lying... by necro81 · · Score: 4, Informative

      Pedantically you may be correct. Cartographically, however, Antarctica is, in fact, divided into East and West. The feature that divides them is the Transantarctic mountains. See this map. West Antarctica contains the Antarctic Peninsula (which stick out towards South America) and most of the floating ice sheets. East Antarctica contains the broad, high plateau containing most of the land ice.

      More generally, the dividing line could be said to be the prime meridian. Places whose coordinates are given using west longitude are generally part of West Antarctica. Most maps of Antarctica are oriented with the prime meridian pointing up towards England. Things on the left side of the map are West Antarctica, the right side is East. Again, this is just a general convention - a way to get yourself oriented. (Even though McMurdo Station (77.8 S 166.6 E) would be in East Antarctica by this definition, it is traditionally part of West Antarctica because it lies on that side of the Transantarctic mountains.)

      This is a cartographer's convention - giving names to places - and it has a particular European bias. But everyone that works in Antarctica uses the same naming convention, so there you go.

    2. Re:They're lying... by Type44Q · · Score: 4, Insightful

      Pedantically you may be correct.

      In my defense, I was trying to be funny (I hardly expected to be modded insightful though I suppose I do have my moments here and there). :)

  6. Re:So what you're telling me by chmod+a+x+mojo · · Score: 4, Informative

    In some ways you are correct. Depressurization is one of the 3 big ways to generate a melt (magma). Just in case you wonder, the other two ways are 1:simply add heat, and 2: add volatiles such as H2O or CO2.

    But the isostatic rebound being fast enough for us to see it in our lifetime is highly doubtful, same with the resulting melt travel time to possible eruption. What they are seeing now most likely is melt from more than just a few years ago.

    Disclaimer: Undergrad Geologist, not PhD yet.

    --
    To err is human; effective mayhem requires the root password!