Horn of Africa - NEW Rift or Mountain from Nabro through Shibiris

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posted on Jun, 21 2011 @ 12:43 AM
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reply to post by youallcrazy
 


Thank you for this more constructive post.

Allow me to ask you a very simple question about Plate Tectonics. In which direction is the African Continent and African plate moving? Does that fit in with the general Rift theory about the Red Sea? How about the Med?

Consider this. There is something that happened and it is happening now increasingly fast. Africa is running over the weaker Southern parts of the European plate. Between the African plate and the thinner European plate a subduction zone is forming, Europe is diving under the Nubian plate. That only started in the Holoscene period! Now, if this is true, then on Africa you would find three things happening.

A) The Red Sea is closing - because of the more Northern movement of Africa and the Arabian/African place is now not a rift anymore - it becomes a sliding plate action, increasingly under more pressure. Because f build up pressure in this sliding zone - mountain ridges will form.

B) The Horn of Africa is pressing against and resisted by the Arabian plate which can't move more-NE wards. So the Horn will break off, from Africa by remaining in the same location for a while; while main Africa is migrating north. That presure will again cause uplift on the Horm of Africa. Did you see the typical ancient cushion lava on the Horn of Africa. That region used to be under sea (brine) when there were massive magma flows. From an very ancient big volcano which half is now still vissible in Yemen and half in Puntland (Somaliland)

C) As the Western fragmented European plate is now increasing subducted, the pressure on the Northern African plate is rapidly reduced, thus you will find increasingly new volcano's and eruptions in Northern Africa. North Nubian plate will 'pick up speed' and there will is a new rift forming in line from Morocco towards Northern Chad.

In effect the theory we had is that Africa is going to break up in 4 pieces, see map below. Now, please do consider this big picture then go back to the most interesting portion where all of this theory starts to be proven today - Eritrea/.Djibouti/Yemen triple Junction which is no more a rift zone on tectonic plate level, though the crust is still expanding because of magma flow (Intrusion) between crust and tectonic plate.

I am sure with this in your mind it should take you no more than a few minutes to see the possibilities.





posted on Jun, 21 2011 @ 01:11 PM
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reply to post by Aromaz
 


As a quick answer, you are confusing relative plate motion with absolute plate motion.

The African plate is moving East or NE RELATIVE to the N. America and S.America plates but it is moving SW RELATIVE to the Arabian plate.

In terms of ABSOLUTE motion the African and Arabian plates are BOTH moving to NE, but at slightly different rates.

It is a confusing concept...an easy way to visualize is take a piece of paper, cut it in half, move the two pieces of paper away from each other (rifting), but at same time move both pieces of paper along the table. Relative to each other they are moving apart, but relative to the fixed table they are both moving one direction (absolute motion).

here is pretty good description of difference from www.delmarlearning.com...


Relative motion
All of Earth’s plates are in motion. For this reason, it’s often easier to
describe a plate’s motion relative to a neighboring plate.
For example, if you were standing on the eastern edge of the African
plate looking at your dog Ralph (sitting very patiently) over on the
bordering Indian-Australian plate, Ralph would appear to be moving
away from you. To Ralph, he is the one sitting still while you move away
from him. The motion is relative to the observer’s point of view, or
frame of reference. In actuality, however, this type of motion would
occur over a very long period, geologically speaking.

Absolute motion and hot spots

When talking about entire plates, scientists often prefer to describe the
plate motions relative to a common frame or point of reference. Ideally,
this reference point is not moving like the plates but is stationary, or
fixed, deep within Earth.

There are approximately 20 places around the Earth where the mantle
below the lithosphere is unusually hot. These hot spots partially melt the
plates above them, creating topographic bulges and chains of volcanoes.
Although their origin is not completely understood, hot spots appear to
be stationary and provide a frame of reference for measuring absolute,
or true, plate motions.

Two of these hot spots are located in the United States. One is under the
Big Island of Hawaii at the southeast end of the Hawaiian Island chain.
The other is in Yellowstone National Park and is responsible for the
volcanic and geothermal activity in that region.

Studying plate motions in a fixed frame of reference provides scientists
with a better understanding of the forces that drive plate tectonics.
edit on 21-6-2011 by youallcrazy because: (no reason given)


here is a paper that uses GPS measurements to show present day rifting continues, unfortunately technical as hell and have to know when they switch back and forth between relative and absolute plate motions
www.umt.edu...
edit on 21-6-2011 by youallcrazy because: (no reason given)





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