reply to post by PaR3v
I think that the central problem with many of these natural-disaster-type predictions is that they cater to (or pander to) the common mentality -- or,
if you like, what's pereceived as the average level of general knowledge about the subject at hand.
The California "big one" quake predictions are a case in point. It's pretty well known that sooner or later the San Andreas fault will let go again
with a "big" quake in or around the magnitude 7 range and depending on exactly where it strikes, it could cause very significant destruction and
possibly some serious losses in terms of human lives. This has been pushed time and time again, so even the more ignorant in the US (and many other
places) are aware of this scenario and pretty much expecting it to happen.
So, very often, the quake-based disaster predictions for the PNW of the USA -- and most often specific for California -- are built around the fact
that most people understand that the thing is going to happen anyway. This gives these predictions a greater air of credibility from the point of view
of predicting something that is widely known to be possible, which allows them more air time in the MSM, for one thing, and somehow sets them apart
from the Blossom-Goodchild-style predictions which are based upon events that a fair slab of the population does
not believe are possible to
begin with.
But the problem is this: while it's true that sooner or later, a fault within the San Andreas fault system** will let go with around a mag 7 quake,
that event is by no means either the largest in energy release or the most catastrophic in terms of human lives and property loss, that is possible
within the US Pacific Northwest. There is in fact the potential for a quake in the magnutude 9-plus range on another fault system, but because it has
been 310 years since the last magnitude 9 quake occurred there, it's not of such apparent interest to the general public.
I'm referring the to the "stuck" section of the Juan de Fuca plate, a smallish plate off the Oregon/Washington coast that has been subducting beneath
the Nth American plate for thousands of years now. The last time this plate's near-coast subduction zone let go in a big way was on Jan 26, 1700 --
the date known from records in Japan, where they recorded details of the tsunami that swept ashore there after crossing the Pacific Ocean. The tsunami
was 30 metres high (almost 100 ft) as it rushed into the Oregon/Washington coast and it floodefd fresh-water lakes miles inland with sea water and
killed the trees. It's the dating of the trees that gave us the year; the Japanese records and local native American lore helped to narrow down the
exact day.
In short, many native villages by or near the coast were inundated by the tsunami and simply swept away. The height of the coastline was changed. The
actual section of land beneath the sea that moved was maybe 600 miles long.
The quake was estimated at a magnitude 9.
To put this in perspective, a magnitude 9.0 quake would release about 1,000 times more energy than California's expected mag 7 "big one". In other
words, it takes 1,000 magnitude sevens to equal the energy that lets go in one magnitude nine quake!
Such a massive near-coastal quake off Washington, Oregon and California (and by the way up into Vancouver as well) would cause devastation in that
region far greater than anything known in the history of the USA. (The last big one happened there before the US actually existed as a soveriegn
nation.) The tsunami would spread hundreds of miles up and down the coast from the epicentre, the shaking in the coastal regions near there would also
be massive and could even cause the soils in some places to liquefy, near-coastal roads would be gone or rendered unusable, along with all the other
infrastructure, casualties could be massive (especially at night), and aftershocks would probably be many and also quite huge.
To make matters worse, it is unknown if a shift of that plate's subduction zone would trigger other quakes in systems like the San Andreas, but it's
not impossible, especially as the final line of the San Andreas runs out into the sea and meets with the fault line that is directly connected to the
Juan de Fuca.
Why am I telling you all this? Because it's simply not so well-known, and also because it illustrates my point that a much worse quake scenario in
that region is rarely mentioned in these disaster predictions -- and that's because of my first point...
The Juan de Fuca has let go with huge quakes several times in the past. The geologists and seismologists know it. They also know it could let go any
day. It could be today or 100 years from now, but it will happen sooner or later.
That is the
real "big one", and I bet the vast majority of people living in that part of the world are barely aware of it.
So, the prophets of doom barely mention it.
As for the Madrid fault, I'll leave that for another day. Suffice to say that it's had mag 8 quakes in the past (during US history) and has now been
quiet for 200 years. I'd be worried about that if I lived there. Not alarmed, but aware and ready to bug out.
Mike
Note: **The "San Andreas" is not really just one fault, but a large system comrising many faults that are geologically and seismically related in some
ways. Their interrelationships are so complex that it's very hard to derive an accurate "shock at point A might trigger a shock at point B" kind of
scenario.
edit on 29/12/10 by JustMike because: Typo. Yes I know there are others, but this one made the subject phrase incomprehensible. The others you
can surely deal with.