Caption: In Yellowstone, the rim of a supervolcano caldera is visible in the distance.
Credit: Credit: National Park Service.
Usage Restrictions: None
Posted on 11/15/2011 2:30:25 PM PST by decimon
The geological record holds clues that throughout Earth's 4.5-billion-year lifetime massive supervolcanoes, far larger than Mount St. Helens or Mount Pinatubo, have erupted. However, despite the claims of those who fear 2012, there's no evidence that such a supereruption is imminent.
What exactly is a "supervolcano" or a "supereruption?" Both terms are fairly new and favored by the media more than scientists, but geologists have begun to use them in recent years to refer to explosive volcanic eruptions that eject about ten thousand times the quantity of magma and ash that Mount St. Helens, one of the most explosive eruptions in recent years, expelled.
It's hard to comprehend an eruption of that scope, but Earth's surface has preserved distinctive clues of many massive supereruptions. Expansive layers of ash blanket large portions of many continents. And huge hollowed-out calderas – craters that can be as big as 60 miles (100 km) across left when a volcano collapses after emptying its entire magma chamber at once – serve as visceral reminders of past supereruptions in Indonesia, New Zealand, the United States, and Chile.
The eruption of these prehistoric supervolcanoes has affected massive areas. The magma flow of Mount Toba in Sumutra, which erupted some 74,000 years ago in what was likely the largest eruption that has ever occurred, released a staggering 700 cubic miles (2,800 cubic km) of magma and left a thick layer of ash over all of South Asia. For comparison, the quantity of magma erupted from Indonesia's Mount Krakatau in 1883, one of the largest eruptions in recorded history, was about 3 cubic miles (12 cubic km).
(Excerpt) Read more at eurekalert.org ...
Credit: Credit: National Park Service.
Usage Restrictions: None
Famous last ping.
As always...
...We’ll always have Niburu.
Who is claiming there will be a supervolcano eruption in 2012?
Looking at that map one thing becomes clear. Aside from most of southern California, it is likely to wipe out most of the good folks in the middle of the country. Too many liberal survivors, NE in particular.
Santorini Eruption Much larger Than Originally Believed
Santorini eruption much larger than originally believed; likely had significant impact on civilization
KINGSTON, R.I. – August 23, 2006 – An international team of scientists has found that the second largest volcanic eruption in human history, the massive Bronze Age eruption of Thera in Greece, was much larger and more widespread than previously believed.
Toba...Toba...Toba
Let’s not have a Toba party.
Based on zero points of emperical data......
It's Always Something (IAS)
I found this:
2012 Completes 74,000 Year Cycle Of Super Volcano
2012 completes a 74,000 year cycle of super volcano – all signs point towards a massive under water eruption
The underwater volcanoes are increasing exponentially. The harmonic tremors are also on a steep rise. A 74,000 year cycle of devastating super volcano nears as we approach 2012. The December 2004 Tsunami epicenter points towards a possible site for the super volcano.
Of course, a harmonic convergence and the well-known 74,000 year supervolcano cycle. Shall we throw the Mayan calendar in for good measure? :-))
How disappointing. We haven’t had a good one since mt. saint helens.
|
Have you heard about the lively new eruption in the Congo.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.
