Feel free to quote. Just include proper accreditation.
It's amazing how much we as people ass-u-me the earth beneath us
is solid and will never move or even twitch. We build houses of
stone, one piled upon another, and expect the resulting stack to last
for hundreds of generations ... and often they do, if not torn down,
blown apart, or destroyed by fire, flood, or war.
We build railroad tracks, clear across two thousand miles of
country, where an extra inch of difference could spell instant
disaster for speeding trains going 50-60mph, without ever expecting
anything to change all along that route. Oh, it's true that we build
in certain "leeway" to allow for thermal expansion from temperature
extremes, wind and other effects on bridges and such ... But the
assumption is that the "real" distance between two towers on each side
of a gorge won't change more than a few fractions of an inch in
centuries.
The assumtion is that this world we live on is SOLID ... A "solid
block of rock". Yet we all really know better.
Far from the earth being solid, it's a semi-plastic surface with
semi-solid scum floating on a mainly liquid ball spinning lazily
through space. Yes, *liquid*. Go down a mere two or three miles, and
the pressure and heat grows intense enough that "solid" rock flows
like putty. Go down 40 miles or so, and the distinction between
"solid" and "liquid" materials matters only when contemplating diamond
crystals. The Earth however, is about 4,000 mile thick, or about 100
times that depth of sloshy liquid. Even cobalt steel in the interior
is quite liquid at that depth; though there's some indication at the
very center pressure forces some kind of true solidity to some parts
of the core. It's the very liquid nature of the core (I understand
anyway) that allows us to have a geomagnetic field ... what we use to
give us compass-directions. Without the core being liquid, the dynamo
that drives the Earth's magnetic field would stop.
The very roundness of the earth (or to be correct, its
oblateness) is determined by gravity and spin ... holding the Earth to
the balance of the two forces to a roundness within one part in 1000;
as few mountains indeed exceed 5 miles in height.
Since the Earth has internal heat (generated from the star-stuff
it's made of ... the remaining tiny bits of Uranium and other leftover
radioactive materials gathered in from star-shit in this neighborhood
when the Sun and planets formed about 4-5 billion years ago) that is
continuously generated, it keeps the interior liquid ... and drives
convection currents like a pot slowly simmering.
People talk about "plate tectonics" and the "conveyer belt" of
the oceans ... but all that is, is the veiw we get from the top. It's
just the slow roiling of an established pattern of heat circulation.
And the "solid" Earth we live on, that set on top of the whole
thing? That's the scum" that's been scraped off the top of the kettle
over billions of years ... the LIGHT shit that floated to the top and
wouldn't go back down with the good stuff. We live on the
"continents" ... The light scum floating on the surface of a liquid
planet. It SEEMS solid to us; but is anything but. Mountains build
and subside over millenia (which to the billions of years of the life
of the planet are tiny periods of time indeed). Oceans open and are
filled in. The scum rises and settles. As things get cold and snow
packs build to mountain heights (what we call "Ice ages") the
mountains themselves are pushed down into the liquid underneath ...
and then rebound when the ice-pack melts.
The scum on the surface is always moving, always jiggling, always
adjusting to the pressures of the moving liquid underneath ... and in
no way is truly stable. Bubbles pop. Mountains slide. Cracks
appear. Pressures build until the scum cracks.
Then we have mountains that blow their tops ... Small mountains,
like Mt. Saint Helens, Bigger ones like Tambora or Krakatoa, or
humongous ones like the one that produced the Yellowstone Caldera.
When things blow or jiggle really badly undersea, we get Tsunamis
or "Tidal Waves" from a few tens of feet high to close to a thousand
feet high. All caused by (comparitively) tiny slippages in the
"solid" earth beneath us. A small earthquake can cause a *big*
landslide under the sea; making a disaster of a wave out of all
(apparent) perportion to the actual quake itself. Around the world
today there are at least half a dozen *major* disasters waiting to
happen ... on the scale of a major meteorite strike on a large city
... and yet hardly anybody is watching. The disaster this week
(Mid-December 2004) in the Indian Ocean is just a *tiny* hint of the
things that could hit. Yet we pay more attention to the possibility
of a rock hitting us from space than we do to the more real threat of
a Tsunami completely wiping out the East coast of the USA, with no
warning at all to evacuate, when we COULD have relatively cheap
warning systems in place globally, like Japan, Alaska, and Hawaii have
done for most of the Pacific.
Why not? Because we *know* the earth is solid. It always has
been, and always will be.
Yeah ... right.
Harry Truman, living on Spirit Lake, said something like that, just
before St. Helens blew.
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