http://www.state.nd.us/ndgs/Rebound/...%20Rebound.htm
Says:
"The greatest measured rates of isostatic or postglacial rebound in North
America occur in the Richmond Gulf area of southeastern Hudson Bay
(presumably where the ice was thickest). There, a kind of "staircase" of
185 Holocene (postglacial) strandlines (former shorelines) provide a
continuous record of emergence from about 8,000 years ago until the present.
At least 935 feet of recovery (isostatic rebound) has been recorded by these
strandlines. By determining the age of these strand lines, and by
subtracting the apparent component of uplift due to relative sea level
fluctuations, geologists have been able to measure rates of isostatic
rebound. The rates of uplift have declined from a maximum of 33 to 39 feet
per 100 years immediately following deglaciation (8,000 years ago at Hudson
Bay - in North Dakota deglaciation occurred about 5,000 years earlier) to a
current rate of about 4.3 feet/100 years. In other words, the shoreline at
Churchill, Manitoba on the shore of Hudson Bay is currently rising about 4.3
feet per century."
Not only are you remarkably wrong in your statements, the fastest North
American rebound on record is right under your own two feet! And you've shot
both of them!
You are not even a barstool geologist! The only rocks you've ever
encountered are in your head!
Is that enough of a beating or do you want some more?
Amen!
Bob Crantz
"Overproof" wrote in message
news:PBKAd.35229$dv1.16823@edtnps89...
Isostatic rebound is not uniform.... it is the result of removal of
pressure from Glacial encroachment. It is entirely subject to underlying
geomorphology
No accurate data exists beyond about 50 years ago.... the data is
interpolated from archeological investigation is based on proximity to
water
of ancient campsites.
The Laurentian Shield is not undergoing isostatic rebound at the rate you
posted.
If this were so...... we could buy sea frontage and expect our investment
to gain a meter every hundred years. I can assure you nobody has reported
such gains in the last 3 centuries.
The mid Atlantic Ridge is the opposing the subduction of the Pacific
plates.
Now cry to your God about how unfair life is and that Creationism is still
a
viable explanation of mankind's evolution.
Fanatics!... Phffft!
CM
"Bob Crantz" wrote in message
link.net...
You fool! The isostatic rebound of the Laurentian Shield is quoted as
1-2
cm/yr:
http://travesti.eps.mcgill.ca/~olivi...es/node43.html
Plus there's other rebounds of at least 2 inches per year! If rock had
the
coefficient of restitution that you quote there would be no earthquakes
over
magnitude 4! You, sir, are no arm chair geologist! Your chair has no
arms,
you are a barstool geologist!
Amen!
BC
"Overproof" wrote in message
news:SBHAd.24735$Y72.23238@edtnps91...
Look you closet geologists...... if the friggin continent of Australia
or
any related tectonic plate subduction resulted in a land mass move of
that
severity in such a small time frame.... we'd be facing much greater
cataclysmic disturbances than an oceanic shock wave.
35 meters?...... Not! Hell... even the severest case of isostatic
rebound
doesn't amount to more than a centimeter every century.
"Aniculapeter" wrote in message
...
You didn't answer any of my questions.
There were only a earth quake in the western end of the plate.
The north part of New Zealand is on the same tectonic plate as
Sumatra,
but
not on the same tectonic plate as the southern part, and I think it
would
not have gone unnoticed if half of the Northern Island (Auckland) had
moved
36 meter relative to the other half (Wellington). (yes they are on
different
tectonic plates).
So I can't see that it is simply the matter of the hole plate moving
36
meters.
Anyway my question was about the consequences for navigating the
area,
using
GPS.
I also find it interesting to find out how the whole plate moved, but
I
can't se that it could be as simple as you suggest.
Does any of our colleagues down under se any change in their GPS
positions
?
Peter S/Y Anicula
o
Capt. NealŪ skrev i en
...
Understand this. Not just isolated islands moved. The entire
tectonic
plate
in the area of the quake subsumed and everything on this plate moved
along
with the plate. If the tectonic plate moved three meters then
Australia
moved three meters provided the whole of Australia is on that plate.
Pate tectonics are not hard to understand. Since Pangea plates have
moved.
Over the millennia Pangea broke up into the continents we see today
which
are
pretty evenly spaced around the globe.
CN
"Aniculapeter" wrote in message
...
I heard that the island of Sumatra has moved 35 meter.
Is or was there any anomalies in GPS positioning on the
"Australian
Plate"?
Is it regulated by the satellites ?
As far as I can guess, a datum change would be necessary ?
Does anybody know any reliable sources for answers to these
questions
?
Peter S/Y Anicula