Good search job Snowbird!
Let's start with the ancient lore about wandering volcanoes:
During their voyages, sea-faring Hawaiians noticed the differences in erosion, soil formation, and vegetation and recognized that the islands to the northwest (Niihau and Kauai) were older than those to the southeast (Maui and Hawaii). This idea was handed down from generation to generation in the legends of Pele, the fiery Goddess of Volcanoes. Pele originally lived on Kauai. When her older sister Namakaokahai, the Goddess of the Sea, attacked her, Pele fled to the Island of Oahu. When she was forced by Namakaokahai to flee again, Pele moved southeast to Maui and finally to Hawaii, where she now lives in the Halemaumau Crater at the summit of Kilauea Volcano. The mythical flight of Pele from Kauai to Hawaii, which alludes to the eternal struggle between the growth of volcanic islands from eruptions and their later erosion by ocean waves, is consistent with geologic evidence obtained centuries later that clearly shows the islands becoming younger from northwest to southeast.
... and the earliest contemporary idea about a plume:
J. Tuzo Wilson's original diagram (slightly modified), published in 1963, to show his proposed origin of the Hawaiian Islands. (Reproduced with permission of the Canadian Journal of Physics.)
Posted by Snowbird
(here)
I found that this very area is where scientists have discovered the extended plume of molten rock. I also read that the concept of mantle plumes is scientifically controversial.
Yes, indeed, the plume theory, even with Hawaii, was well into a coffin and nailed in... but, the fiery Goddess Pele resurrected and kicked that coffin lid off and away:
Hawaiian Hot Spot Has Deep Roots
ScienceDaily (Dec. 3, 2009) — […] Now, a sophisticated array of seismometers deployed on the sea floor around Hawaii has provided the first high-resolution seismic images of a mantle plume extending to depths of at least 1,500 kilometers (932 miles).
"This has really been an eye-opener," says Solomon. "It shows us that the anomalies do extend well into the lower mantle of the Earth."
Has the question of hot spots and mantle plumes been settled at last? "We believe that we have very strong evidence that Hawaii is underlain by a plume that extends at least to 1,500 kilometers depth," says Solomon. "It may well extend deeper, we can't say on the basis of our data, but that is addressable with global datasets, now that our data have been analyzed. So it's a very strong vote in favor of the plume model."
Journal Reference:
C.J. Wolfe, S.C. Solomon, E.H. Hauri, G. Laske, J.A. Orcutt, J. A. Collins, R.S. Detrick and D. Bercovici. Mantle Shear-wave Velocity Structure beneath the Hawaiian Hotspot. Science, December 4, 2009
From: http://www.sciencedaily.com/releases...1203141905.htm
We have known about the possibility of the Yellowstone supervolcano for years. We are simply learning more about it. Knowledge is powerful even though it may or may not stem from one who is certified or licensed. The reason that we have these discussions on line is to learn from one another.
I totally agree that knowledge gives one more control/power over doom and gloom. My concern with the dutchsinse video is that he presents the diagram as a plume of molten rocks rather than of hot, salt saturated fluids (see original article).
For Yellowstone, here is the most recent seismic model (2009):
Caption: This is a cross section of the plume of hot and molten rock that tops out about 50 miles beneath Yellowstone National Park, and tilts downward to the northwest to a depth of at least 410 miles. The plume is mostly hot rock with about 1 to 2 percent molten rock. Researches believe "blobs" of hot rock slowly detach from the top of the plume and rise upward to recharge the magma chamber that lies from 3.7 to 10 miles beneath Yellowstone. The chamber is also mostly hot rock, but with a sponge-like structure containing about 8 to 15 percent molten rock.
I also read that it is possible that the state of Oregon could have been positioned where Yellowstone is currently, seventeen million years ago. That's a lot of repositioning of the earth's crust over time. Which makes one wonder just whether or not the plumes of molten rock remained stable or traveled. .
… a preliminary study by other researchers suggests Yellowstone's plume goes deeper than 410 miles, ballooning below that depth into a wider zone of hot rock that extends at least 620 miles deep.
They saw overlap, between the zones within the Earth where eruptions originated near the Oregon-Idaho-Nevada border and where the famed Columbia River Basalt eruptions originated when they were most vigorous 17 million to 14 million years ago.
Their conclusion: the Yellowstone hotspot plume might have fed those gigantic lava eruptions, which covered much of eastern Oregon and eastern Washington State.
From:
http://www.eurekalert.org/pub_releas...-ype121109.php
There are ancient extinct calderas all over the U.S. There is at least one in New Mexico and another about 15 miles from Mt. Baker in Washington state, which was a supervolcano. Many of these extinct volcanos are not easily visible
These are the current recognized hot spots/plumes world wide. What's known with certainty is the relative displacement between crust and plume. What's unknown is if the plumes are totally fixed as in the 19 degrees latitude thing or wandering as in the shift of the magnetic poles would indicate. To be resolved.
My opinion on the Yellowstone threat is that it would be less explosive (but still catastrophic) than at the time of the original formation of the caldera, simply because the channels are already in place which wasn't the case at the time of the first intrusion. Now, in the case of a new crustal shift with respect to mantle, that would be another story... because that would require another outlet to be punched through.
Hope this helps clarify the matter better?
Yellowstone Announced to be Much Bigger Than Originally Thought
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