> The most significant recorded volcanic explosion since the Holocene took
> place in 1257/58. It was magnitudes larger than the Krakatoa explosion,
> which was dwarfed by the 1815 Tambora explosion. It precipitated the Little
> Ice Age by injecting so much debris into the atmosphere that global
> temperatures slowly decreased until the mid-19th century. The Little Ice Age
> was the result of this long-term cooling plus the complete lack of solar
> activity during the Maunder Minimum.
Hmm. Right to the time of the industrial revolution! Hmm. Wait a
second. Isn't global warming blamed on the industrial revolution? This
can't be right... Ah, I get it. The industrial revolution is what was
required to return the global climate to the normal state.
Except, what is "normal"? Mega volcanic explosions have occurred
throughout the history of the planet and appear to be the great
climate leveler. If it wasn't for the volcanoes occasionally spewing
their ash up into all layers of the atmosphere (I'm waiting for NASA
to officially report that the particle sensors on the ISS have
detected volcanic particles), we'd be a whole lot warmer.
Every other week, I travel up into the mountains for an evening of
driving, hiking, photographing and 4-wheeling. To get where I'm going,
I pass through the "Hogbacks". This is a ridge formed from an uplift
with the exposed rocks coming up from something like three miles
below. I'm thinking that the earthquake that occurred when that
happened was probably a bit on the scary side. That surely would have
caused the ice cubes in a glass of ice tea to tinkle. It is likely
that an earthquake like that would have been felt world wide. A lot of
our geology would have been formed by major events like that. A
popular theory, taught in our schools is that geological features like
that would have occurred over thousands of years because we haven't
seen an earthquake move anything for than 20-30 feet in our lifetimes.
What is so wrong with those theories is that erosion would have
destroyed it while it was being created. In Montana, south of Glacier
National Park, there are a series of sawtooth ridges that were formed
when a major uplift occured and caused the layers of rock to separate
and slide down hill. What makes it particularily fascinating is that
the layers are not in the right order. There are literally layers of
older rock sitting on top of younger rock.
On a personal note. One of our favorite camping spots in Colorado is
at Chalk Lake/Creek. There is a trailhead there that goes up to the
Agnes Vaille Falls on the north side of the valley. It's a relatively
easy hike and quite popular. I've been up it a number of times and
took one of my daughters up there too. Yesterday, there was a rock
slide that killed five people. The geology is such that there is no
secret that rock slides occur there on occasion--otherwise how would
you explain the extensive rock debris field that the trail traverses?
Anyway, a little "close to home" for me. Unknown if all the recent
heavy rains have affected the slide area, but I suppose that you need
outlier conditions to move things around which sit still during normal
conditions.
--
Ken Norton
ken@xxxxxxxxxxx
http://www.zone-10.com
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