Mt. Hood in Oregon, taken August 2008. Image by Erik Klemetti. Click on the image to see a larger version.
- I'm not going to go into too much depth right now about the recent study published in Nature Geoscience on Mt. Hood in Oregon - I plan to talk about it more in a few weeks. Why is that? Well, the lead investigator on the study, Dr. Adam Kent of Oregon State University, is a friend of mine (and occasional Eruptions commenter) so I plan to get the details from him before posting. I was also peripherally associated with some of this work - mostly in the field acting as a pack mule and offering my witty observations. Nevertheless, the long-and-short is that magma mixing seems to be a strong control on eruptions at Mt. Hood, where mixing of two different magmas (one felsic, one mafic) can trigger an eruption. This mixing could be only weeks before the eruption, suggesting short time intervals between the trigger of an eruption and the eruption itself. Interestingly, Mt. Hood seems to play by its own rules in this respect relative to what we know about how other Cascade volcanoes behave.
- Lava continues to flow from Kilauea into the area around Kalapana, although it has slowed. Only two breakouts were noted near Kalapana on August 1, suggesting that less lava is flowing. However, lava continues to reach the ocean to the southwest of Kalapana.
- PHIVOLCS lowered the alert status at Taal to level one after signs of eruption waned, with only 5 earthquakes over the last 3 weeks. However, the restrictions for tourists remain in place for the time being as new measures are created, especially when it comes to approached the main crater. At the crater, steam explosions can still happen unexpectedly and the concentrations of volcanic gases can be dangerous.
- The NASA Earth Observatory posted an image of the plumes from Ambrym and Gaua in Vanuatu. You can see the thin, wispy plumes of mostly steam and volcanic gases (which possibly some very minor ash) drifting to the northwest.
- Log in to post comments
So if there is an earthquake swarm at Mt Hood it would be best to take notice earlier rather than later.
Here is the abstract of an interesting paper. I wonder if the full paper gives any specific info on plate tectonic differences below Mt. Hood? (From mantleplumes.org)
Xue, Mei; Allen, R.M., Mantle structure beneath the western United States and its implications for convection processes, J. Geophys. Res., 115, No. B7, B07303, 2010.
@2: No, it's a 'Big Picture' type article. Better reads on the cold mantle down-welling process under Western US:
Dripping 'Blob' Under Western U.S.: A Hidden Drip, Drip, Drip Beneath Earth's Surface. Science Daily May 2009
John D. West, Matthew J. Fouch, Jeffrey B. Roth, Linda T. Elkins-Tanton. Vertical mantle flow associated with a lithospheric drip beeath the Great Basin. Nature Geoscience 2, 439 - 444 (2009) DOI: 10.1038/ngeo526
(full paper below)
Western USA mantle structure and its implications for mantle convection processes. (same authors as paper cited by Pyromancer)
"Nevertheless, the long-and-short is that magma mixing seems to be a strong control on eruptions at Mt. Hood, where mixing of two different magmas (one felsic, one magma)"
I am assuming you meant one felsic, one mafic...or did you mean that a felsic magma can interact with any other type to trigger an eruption?
@VolcanoMan - Oops, thanks for catching that. It was supposed to say "mafic". Will fix it now.
I have been waiting for someone with a bit of knowledge to write about the long series of quakes we have been seeing at TFZ (about 10 km north of GrimsÃ¶y).
It has after all been going on for more then 2 weeks now without letting up.
The action is not situated at the site of the 1868 underwater eruption, it is to the nort-west to it. Lurking did a nice picture of it a week ago that seemed to show that it was a pipe pattern to the quakes.
So, anybody with a take on this? Is it an eruption, or a what?
Looking forward to any answer.
Hey that's an amazing insight on the subject, thanks so much! never heard it more clear.
A sense of humor... is needed armor. Joy in one's heart and some laughter on one's lips is a sign that the person down deep has a pretty good grasp of life.
Just texted my mom to see if she wanted to get pedis after work. It was only after I sent it that I realized iPhone corrected 'pedis' to 'penis'. I asked my mom if she wanted penis after work. Brilliant.
I hope that guy that "wants to be a billionaire" makes $999,999,999.00 and then gets hit by a bus
You must never promote a journey of revenge without giving a lunatic : Confucius
Things you mentioned made . Nevertheless, think about this, what happens if you offered a little more? I mean, I do not want to teach the way to write your site, but if you actually added something which can grab people's focus? Simply like a video or a graphic or few for getting viewers psyched about what you are talking about.
Very useful article. Myself and my neighbor were getting ready to do a little study regarding that. We bought a helpful guide on that issue by our own neighborhood library and many publications are not as descriptive as your content. I am very thankful to discover such info which I was searching for a long time.