Yellowstone Hot Spot Shreds Ancient Pacific Ocean

jamie passes along this excerpt from DiscoveryNews: "If you thought the geysers and overblown threat of a supervolcanic eruption in Yellowstone National Park were dramatic, you ain't seen nothing: deep beneath Earth's surface, the hot spot that feeds the park has torn an entire tectonic plate in half. The revelation comes from a new study (abstract) in the journal Geophysical Research Letters that peered into the mantle beneath the Pacific Northwest to see what happens when ancient ocean crust from the Pacific Ocean runs headlong into a churning plume of ultra-hot mantle material."

Re:Gulf of Mexico

[thomst]

A lot of people don't realize the gulf of mexico was formed by a giant hot spot like yellowstone.

Unless it wasn't [aapg.org](pdf).

Re:Fix Wikipedia, please

[bunratty]

No, forum posts are not reliable sources. Neither are blogs or self-published websites. In general, what Wikipedia considers to be a reliable source [wikipedia.org] is a publication that has some sort of editorial control, such as a traditional newspaper or periodical, book published by a traditional publishing company, or a company's official website. That means that you can't just publish your own newsletter or book or website and then cite it in Wikipedia.

Re:Flood basalts

[Anonymous Coward]

It's a reasonable hypothesis. There is a track of age-progressive volcanism from the Columbia River Basalts to the Snake River Plain, leading up to Yellowstone today. I know there are legitimate questions about it, but it's certainly a coincidence in timing and location if the Columbia River Basalts *don't* have something to do with the hotspot that is now thought to be beneath Yellowstone. Geologists would have to come up with some other explanation for the large amount of melt generated in the mantle to produce the Columbia River Basalts.

There have been questions about the nature of hotspots generally for long time (some people question whether they really exist -- hotspots certainly are hard to image geophysically), but the fact that *something* seems to leave a trail of volcanic centers across both continents and ocean floor that varies in age along the track is pretty consistent with something unusual happening in the mantle underneath. A good example is the trail of kimberlite pipes across northern Ontario [nrcan.gc.ca] (the ones east of Timmins), intrusives in southern Québec (the Monteregian Hills [wikipedia.org]), the intrusives in the White Mountains [wikipedia.org] in Vermont & New Hampshire, and then the New England Seamounts [wikipedia.org] offshore, until the trail [wikipedia.org] hops across the spreading ridge to the African side of the plate. That's a pretty persistent trail of volcanism, and there are plenty of other examples, some of which are also associated with flood basalt volcanism like the Columbia River Plateau.

Very cool, but article exaggerates to sound cooler

[penguinchris]

If you look at the illustration in the article (and I assume in the original paper, I have access but have to login to a vpn and so on, I will see later since I'm interested), it's quite clear what happened and it's really not what you might think when you hear it "shredded" a tectonic plate. I think what's being implied is that it shredded the plate at the surface, but it happened far underground, in the mantle.

As the subducting plate subducts, it goes down into the mantle and in this case the mantle plume weakened it (by getting into fractures or whatever) and broke it off. So the slab disappears down into the mantle eventually (though these can stick around for years, detached). It's very interesting, but the same thing often happens without being cut off by a mantle plume. It's more or less a guaranteed result in a subduction zone, because the subducting slab isn't strong enough to support its own weight pulling on it after a certain point. Makes absolute sense if you look at a diagram of how subduction works.

Subducting slabs can also be cut off by things like strike-slip faults, which IIRC happened in northern California as a result of the San Andreas (don't quote me on that though). You can see the slabs in the mantle by various imaging techniques.

IAAGGS

Re:Fix Wikipedia, please

[toastar]

or I could just cite Actual peer reviewed work:
http://aapgbull.geoscienceworld.org/cgi/content/abstract/89/3/311

Yellowstone National Park

[calidoscope]

One problem with tapping Yellowstone is that the geothermal fields are almost entirely within Park boundaries. Do keep in mind that the reason for Yellowstone becoming the world's first national park was to preserve it by preventing development.