I just read in today's paper that the source seems to be Ken Hudnut from the
US-GS. He has been quoted for saying something like:
"The earthquake changed the world map"
"Small islands in the Indian Ocean has been moved up to 20 meters, while the
north-western tip of Sumatra may have moved up to 36 meter."
(my translation from the Danish translation).
Erik Schou Jensen, from The Geological Museum at the University of
Copenhagen, thinks that Ken Hudnut has been misquoted, and says:
"What he (KH) is talking about, is a small splinter (?) of a plate located
on the sea-bottom north of Sumatra. This, he (KH) thinks, can have moved up
to 36 meter"
"It has not been possible to perform the necessary measurements, since the
Indonesian authorities has closed the whole area down (?) but the island can
have moved a few centimeters..."
"During the earthquake, it was the Indian plate that slid down under the
plate with Sumatra, so it would not have been Sumatra that moved, but the
sea-bottom under the Indian ocean and not more than five to six meter at one
time."
So it looks like it was just another example of the press not being able to
present the facts.
Peter S/Y Anicula
Overproof skrev i en
nyhedsmeddelelse: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
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