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Ethiopia, geology of (including moving mountain)

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Jenny
158937.  Thu Mar 22, 2007 12:52 pm Reply with quote

Words back from my geology professor friend (Annie Rassios) in Greece, regarding some of the things on this thread, which I ran by her. Her comments in capital letters:

Ethiopia will one day become an island.

I'D CALL IT AN ENTIRELY NEW CONTINENT ACTUALLY - AN ISLAND CAN BE CAUSED BY MANY THINGS SUCH AS DEEPER OCEANS, BUT THIS IS THE BIRTH OF A NEW LANDMASS INDEPENDENT OF THE AFRICAN PLATE.

Africa is breaking into two pieces AS WE WRITE, one part containing Ethiopia and Eritrea and up into Israel, and the other part containing everywhere else, in between will be the African Ocean INCLUDING THE AREA where the Red Sea is now.

The reason Ethiopia will end up as an island is that it is on the Arabian plate, while the rest of the continent is on the African plate.

NO – ETHIOPIA WILL BECOME AN INDEPENDENT TECTONIC PLATE IN ITSELF THAT INCLUDES THE ARABIAN PLATE, JUST AS AFRICA AND SOUTH AMERICA WERE ONCE UNIFIED AND NOW ARE TWO DISTINCT CONTINENTAL PLATES WITH INTERVENING OCEANIC PLATE.

50 million years ago Heart Mountain in NW USA moved 62 miles in half an hour due to a liquid layer of lava and water which accumulated under the ground. It is the same mechanism that some claim will cause mountains in the canary islands to move in the future causing a huge Tsunami which could engulf the
Eastern Sea Board.

THIS IS A STRETCH. HEART MOUNTAIN IS A VERY WEIRD OCCURRENCE, WERE SOMETHING LIKE THIS TO HAPPEN ANYWHERE ELSE WITH OCEAN INVOLVED IT COULD CAUSE HUGE TSUNAMI. I DO NOT KNOW THE EVIDENCE THAT STATES THAT THE CANARIES ARE LIKE HEART MOUNTAIN.


I think Heart Mountain is the key to this one - we make the point about how a million years is a short time on the geological scale, and then cut to the mountain moving at 120mph.

THERE IS NO STANDARD GEOLOGIC SCALE, OR RATES OF MOUNTAIN BUILDING – THEY CAN BE “CATASTROPHIC” IN THE SENSE THAT THEY HAPPEN VERY FAST (WHETHER OR NOT A “CATASTROPHE” IS INVOLVED) OR SLOWLY.

Maybe the context is the research which indicates that mountains can be created more quickly than was thought: 13 million years instead of 40 million in the case of western Norway, for example:
http://www.livescience.com/forcesofnature/050713_mountain_building.html

THE VOLCANIC MOUNTAIN PARACUTIN OF MEXICO EMERGED FROM A CORN FIELD AND GREW NEARLY 8000 FEET IN LESS THAN 10 YEARS. THIS TOO IS A GEOLOGIC SCALE OF MOUNTAIN BUILDING. DIFFERENT GEO ENVIRONMENT.

NORWAY HAS RISEN AT LEAST A HUNDRED METERS SINCE THE LAST ICE AGE “REBOUNDING” FROM THE WEIGHT OF THE ICE SHEET THAT HAS BEEN REMOVED.

Hensen and his colleagues studied the geology of the Southern Caledonides in western Norway. A continental collision occurred there some 425 million years ago, causing certain rocks to be buried to depths of 36 miles (60 kilometers). These rocks have since returned to the surface, where glaciers have ground and polished them.

The researchers found that the time between burial and resurfacing -- called the orogenic cycle -- took 13 million years, instead of some 40 million years as previously thought. The implication is that the mountains themselves grow up faster than expected....

The study was detailed in the June 30 (2005) edition of the journal Nature

THIS SECTION IS FUZZY. TO ME READING THIS I WAS CONFUSED BECAUSE THERE IS NO DISTINCTION BETWEEN VARIOUS PHASES OR ENVIRONMENTS OF MOUNTAIN BUILDING – SORT OF LIKE ANNOUNCING THE PRESENCE OF A FRUIT SALAD WITHOUT DISTINGUISHING BETWEEN THE TIME NECESSARY TO GROW THE DIFFERENT KINDS OF FRUIT AND THEN PREPARE IT IN THE KITCHEN.

NOTE—THE OROGENIC CYCLE HAS NO CONSTANT RATE, AND VARIES BETWEEN GEOLOGIC ENVIRONMENT.
WHAT’S HAPPENING TO THE OLD CONTINENT OF NORWAY REMAINS VERY SLOW COMPARED TO MOUNTAINS FORMING IN, SAY, IN THE SOUTH PACIFIC.


Which mountain was originally enveloped in Earth's mantle?

Mount Olympos in Greece is FORMED OF ROCKS DEPOSITED ALONG the coast of ancient Africa. These were trapped between a plate tectonic collision between Africa and Europe, and pushed down below the European continent to a depth of 35 km. Being of lighter material than surrounding rocks, Olympos arose from these depths, and with the aid of regional tectonism today is the
highest mountain in Greece, rising nearly 10,000 feet directly from the Aegean.

 
Jenny
158938.  Thu Mar 22, 2007 12:53 pm Reply with quote

Whoops - megapost. Sorry :-(

 
eggshaped
158962.  Thu Mar 22, 2007 1:35 pm Reply with quote

Quote:
I DO NOT KNOW THE EVIDENCE THAT STATES THAT THE CANARIES ARE LIKE HEART MOUNTAIN.


This theory came from Dr. Einat Aharonov, Department of Environmental Sciences & Energy Research at The Weizmann Institute of Science.

 
Jenny
158968.  Thu Mar 22, 2007 1:49 pm Reply with quote

Does the phrase 'some claim' cover it? Do you have the source for Dr Aharonov's statement? I can ask Annie to look it over if you like.

 
eggshaped
158972.  Thu Mar 22, 2007 1:57 pm Reply with quote

from foxnews:

Quote:
Aharonov warns that, sitting on a volcanic site, the Canary Islands could be traveling soon — posing a significant tsunami risk.


http://www.foxnews.com/story/0,2933,196226,00.html

So not a direct quote I'm afraid.

The idea that one day the Canaries might cause a mega-tsunami is well versed isn't it? Not saying it's true, but I've certainly heard the claim many times in the last few years.

Of course I added the "some claim" to cover my arse in case my research was quoted in the show. As this is not my area of expertise, and I don't think the claim is without its skeptics

 
Jenny
158982.  Thu Mar 22, 2007 3:00 pm Reply with quote

I'm not sure I regard anything emanating from Faux News as a reliable source, eggshaped. But I'll send the link to Annie and see what she makes of it.

 
eggshaped
159036.  Thu Mar 22, 2007 6:34 pm Reply with quote

Your prejudice about FoxNews may be fair, for all I know, but I doubt the story came from there originally.

MSNBC
Livescience

I chose fox only because it was the first news portal which came up on my google-search.

 
Flash
159043.  Thu Mar 22, 2007 6:49 pm Reply with quote

Jenny - that's great. I reckon we've got the picture more clearly now, and we won't be casual with our facts - but for the purposes of the show I think the only proposition that's likely to be useable by the panel is the fact that a mountain moving at 120mph is highly atypical.

 
eggshaped
159046.  Thu Mar 22, 2007 7:01 pm Reply with quote

Quote:
THE VOLCANIC MOUNTAIN PARACUTIN OF MEXICO EMERGED FROM A CORN FIELD AND GREW NEARLY 8000 FEET IN LESS THAN 10 YEARS. THIS TOO IS A GEOLOGIC SCALE OF MOUNTAIN BUILDING. DIFFERENT GEO ENVIRONMENT.


Is this true? According to EBR, Parícutin only reached 9,210 feet (2,808 metres) in 1952 which is a mere 1,730 feet higher than its original base.

To give people a prospective, 1730 feet is around the height of sears tower.

 
Jenny
159342.  Fri Mar 23, 2007 10:40 am Reply with quote

Eggshaped - I'll ask her to check that. This is the reply I had over the Canaries issue after I asked her to check that Fox News link.

Quote:
My, that’s the first time I’ve ever been to Faux News for any reason!

Reading that article, it’s almost impossible to go back to figure out the science behind it.

“Rock at the summit of Heart Mountain is 250 million years older than at its base. That suggests the top and the bottom have not always been together”

Whoop-de-doo. This statement describes a rather ubiquitous geologic phenomena called a “thrust fault” – these are very common, and place older rocks over younger rocks over a rather low-gradient fault surface. There are also things called “gravity faults” which do much the same, but slide down slope instead of up slope, and tend to go faster.

The rates these faults move can be slow or relatively fast. They tend to have trapped fluids at the fault surface which act as lubricant and help things along. Yes, I would accept as a possibility that a thrust fault could move very fast with the proper lubrication -- I don’t know of such a case, but it’s feasible.

It sounds like Aharonov is stating that the source of the fluids along the Heart Mountain thrust were introduced by volcanic activity. The description of what is dikes (actually spelled dykes for you in Britain) is nonsense so forget that. From the Fox article, I can’t picture at all what’s going on, it just sounds like geologic gobbledy-gook written in such a way as to sound “geologese” to someone who can’t speak the language. So I’d need to get to the source in Geology. I’ll see if I can get into it tomorrow.

The article doesn’t give nearly enough background to judge whether or not something like that could happen in the Canary Islands. Again, I’d need to see the Geology article to read about it in its “native tongue.”

I can’t for the life of me remember where I learned about the cave at Patmos, but wrote it up for a Geomythology book some years back. Let me see if I can find my original sources. It certainly is less a long shot than the Canary Island thing.

Annie

PS Factoids are fun. Oh, what am I? Senior staff scientist at the Institute of Geology and Mineral Exploration of Greece (the Geologic survey of Greece), PhD, and about five pages of citations in the “Scholar” pages of Google. Not a bad number of peer-reviewed science papers for a lady living in a village.

 
Jenny
159343.  Fri Mar 23, 2007 10:42 am Reply with quote

If you all feel this particular horse has been flogged to death, if you like I could ask her to take a look at any question you decide to formulate, to check the accuracy of what we're saying.

 
eggshaped
159366.  Fri Mar 23, 2007 11:11 am Reply with quote

Quote:
The article doesn’t give nearly enough background to judge whether or not something like that could happen in the Canary Islands.


I can't tell whether your friend is claiming that she's never heard of the Canary Island/Mega Tsunami theory (which I doubt, as it's very well known) or whether she's doubting that the mechanics of it are the same as at heart mountain (which would seem much more likely).

Anway, here are some papers:

http://www.swvrc.org/lapalma.doc

http://www.es.ucsc.edu/~ward/papers/La_Palma_grl.pdf

I can't judge whether the mechanism is the same as what was claimed in the above news articles as to be honest it's babble, like most scientific papers. One day, the people who write scientific papers will realise that you're a much better scientist if you are able to explain your findings to the general public.

 
Flash
159375.  Fri Mar 23, 2007 11:18 am Reply with quote

Jenny - I think that's the way to go. We really love having proper experts up our sleeves, and I always think we need to be careful not to try their patience by bombarding them with queries, so they won't mind fielding the questions that really matter when we decide what they are.

 
eggshaped
165648.  Fri Apr 13, 2007 7:14 am Reply with quote

Ranongga island in the South Pacific has been lifted 3 meters out of the sea after last week's earthquake.

Quote:
In some places the beaches in the Solomons now resemble a barren moonscape with once vibrant corals bleaching under the sun.

On one beach the quake even revealed a sunken vessel that locals believe is a Japanese patrol boat from World War II.




link

 
eggshaped
174065.  Mon May 14, 2007 2:43 am Reply with quote

The Hudson Bay area of Canada has lower gravity than other parts of the country.

Apparently it's something to with a huge ice sheet which pushed the earth down before melting. The land in that region is slowly bouncing back.

Quote:
"If the Earth were a perfect sphere, gravity would be the same everywhere around the sphere,"

But the Earth is not a perfect sphere. It's lumpy; mass is distributed unevenly both inside the Earth and on its surface. Thus, gravity varies over different regions.


link

 

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