Yellowstone Earthquakes & Updates on Supervolcano

[Andre]

http://www.usnews.com/blogs/capital...lowstone-earthquakes-supervolcano-update.html

...
1) The rumbling continues, including 3.5, 3.0 and 3.2 quakes just today

2) Here is some more Jake Lowenstern (the Yellowstone volcano scientist) analysis (via TIME):

Jake Lowenstern, Ph.D.,YVO's chief scientist, who also is part of the USGS Volcano Hazards Team, told TIME that it doesn't appear a supervolcano event is imminent. "We don't think the amount of magma exists that would create one of these large eruptions of the past," he said. "It is still possible to have a volcanic eruption comparable to other volcanoes.
...

Not a lot certainty about what's going to happen. Although one thing seems certain, the scary scenarios will accumulate, don't you think?

 

[Xnn]

The three largest Yellowstone eruptions produced a rain of ash that spread over much of western and central North America and beyond; these ash deposits are greater than 2 m thick near their eruptive sources and as much as a meter thick in surrounding areas.

Each of these three eruptions produced a caldera, or deep crater-like depression, tens of kilometers wide, formed by collapse of the ground surface into a partly emptied subterranean magma chamber. The latest of these three great eruptions formed the Yellowstone caldera. Renewed magma influx beneath the Yellowstone caldera in central Yellowstone National Park uplifted parts of the caldera floor and produced voluminous intracaldera lavas, the youngest of which extruded in a series of eruptive episodes about 164,000, 152,000, 114,000, 102,000, and 72,000 years ago.

Available data suggest a highly episodic behavior of past eruptions of this sort, periods of a few thousand years characterized by numerous eruptions being separated by longer intervals of about 12,000 to 38,000 years without eruption. One statistical measure of eruption probabilities based on this episodic behavior suggests an average recurrence of 20,000 years. The fact that no such eruption has occurred for more than 70,000 years may mean that insufficient eruptible magma remains beneath the Yellowstone caldera to produce another large volume lava flow.

Of the hazards, the most likely to occur are hydrothermal explosions, with an average annual probability from as high as 0.5 (equivalent to an average recurrence of 2 years) for small explosions to perhaps 5x103 (an average recurrence of 200 years) for explosions large enough to form a 100-m-diameter crater. Hydrothermal explosions that might result in potential risks to people have a probability no greater than 0.1 per year (an average recurrence of 10 years) for small explosions. Potential for a volcanic eruption is much lower than that for hydrothermal explosions.

Source: http://pubs.usgs.gov/of/2007/1071/of2007-1071.pdf

 

[Astronuc]

Not a lot certainty about what's going to happen. Although one thing seems certain, the scary scenarios will accumulate, don't you think?

I imagine there will be a lot of hype motivated by the desire to sell more advertising. Call me cynical, but I don't see much in the way of critical analysis in the media.

Anything Earth movement around mag 2-3 is not big deal - California and Alaksa have that daily. The more appropriate measure would be temperature rises, which would indicate magma moving toward the surface.

I was in Yellowstone several years ago and I observed that many of the thermal vents and features were no longer as hot or active. Part of that is a shift in the magma, and part may be drier weather so that ground water is reduced in some areas.

 

[D H]

Xnn, those words aren't yours. When you quote verbatim you should always cite the source, which in this case is http://pubs.usgs.gov/of/2007/1071/of2007-1071.pdf.

 

[Evo]

I read this article earlier.

Earthquakes are hardly unusual in Yellowstone. Hundreds occur in the park every year. Earthquake "swarms" like the recent activity also aren't uncommon, although the 900 or so quakes that began Dec. 26 and significantly tapered off about a week later appear to have been the most energetic swarm in more than 20 years.

http://news.yahoo.com/s/ap/20090110/ap_on_sc/yellowstone_volcano_hysteria

 

[Astronuc]

For perspective, see this map.
http://earthquake.usgs.gov/eqcenter/recenteqsww/Maps/region/N_America.php

Note the greater frequency of earthquakes of Mag 2.5 or greater in Alaska, California and Puerto Rico, compared with Yellowstone. In Yellowstone, there is one earthquake of Mag 3.3, which is unusual.

Also see recent earthquakes in the US - http://earthquake.usgs.gov/eqcenter/recenteqsus/
Alaska, California and Puerto Rico have daily activity well above Yellowstone

Zoom into - http://earthquake.usgs.gov/eqcenter/recenteqsus/Maps/US10/37.47.-115.-105.php - and note the number of earthquakes in Utah vs Wyoming (Yellowstone).


Certainly, one should keep an eye on Yellowstone, but don't panic.

 

[hypatia]

Is it better to have many small rumblings, I thought I remembered something along those lines anyways...?

 

[turbo]

Is it better to have many small rumblings, I thought I remembered something along those lines anyways...?

It's better to have regular small quakes on a major fault than to have a long period of quiet, when stresses can build. I would not want to be near the New Madrid fault when that rascal decides to cut loose again.

 

[Evo]

I was watching a show about volcanic action in Hawaii last night, and earthquakes always precede eruptions there, but that is a unique area with a fixed hot spot that the plates move over. Or so they said.

 

[WhoWee]

This has interesting graphics and details.

http://www.solcomhouse.com/yellowstone.htm

 

[Count Iblis]

http://en.wikipedia.org/wiki/Lake_Toba"

 

[Count Iblis]

http://en.wikipedia.org/wiki/La_Garita_Caldera"