Slashdot Mirror
New Ocean being Formed in Africa
PenguinRadio writes "The San Francisco Chronicle is reporting on a 37-mile long fissure that split open in September in the Afar desert in Ethiopia that could be the start of a new ocean forming. The fissure, which grew 8 meters wide in 3 weeks following an earthquake on Sept 14, is now splitting at about 0.8 inches per year, would eventually lead to Ethiopia eastern portions becoming an island in a million years or so. The findings were presented at the American Geophysical Union meeting taking place in San Francisco this week. The BBC reports that formation of a ocean basin is the first step toward developing an ocean, but that it will be millions of years before that could occur."
It's easier to form a new ocean than it is to ask the company for a raise.
fast as fast can be. you'll never catch me.
Shall I tell my kids to bookmark this article then? Just in case they forget when it all started?
Hey I have some great Ocean View Property in the middle of Africa. Email me if you're interested.
Time to snap up some cheap ethiopian desert land. Will be valuable beachfront holiday developments in a few hundred millenia or so.
Oh no... it's the future.
BBC article
Download my free songs!
Maybe we should hurry global warming along to melt the polar ice caps sooner so we have enough water to fill that new ocean.
Borrow money from a pessimist - they don't expect it back.
From Understanding Plate Motions
Where do I sign up for the $1 billion government grant to study this new "ocean"? Since it's going to take a while, I should build a nice palace -- uh, research station -- to observe this natural event.
God is obviously trying to cover up all those embarrassing hominid fossils he missed obliterating in the last flood.
"Even for Slashdot, that was a very obscure reference!" - Anonymous Coward
Within the article it states that many prospective ocean basins fizz out and never really develop into ocean basins.
So, are there reasons to expect that this one will develop into a full fledged ocean? I mean, it is not easy to predict future events, but without some measure of certainty, wouldn't a more appropriate title have been "Giant Fissure in Ethiopia Continues to Grow"?
And now back to natural disasters.
Given the timefram here, how do we *know* its going to be a ocean?
Oceans are pretty damned large. This thing may never surpass 'lake' stage. Or even just a big mud puddle that reverts back to 'land' when it dries up.
---- Booth was a patriot ----
i wonder if the Island of Madagascar got its start this way, if you look at it like a jigsaw puzzle it would fit right in to the east coast of the continent Africa
Politics is Treachery, Religion is Brainwashing
The Afar region has been stretching apart, in the process of forming a new ocean, for the last 10 or 20 million years. Stretching rates in various parts of the rift vary from 6 to 12mm per year. Parts of the Afar region are already >100m below sea level and filled with salt deposits, and the area is faulted extensively, with many tilted blocks of older material and extensive volcanoes (e.g., Erte Ale) related to the stretching (imagine the effect if you stretched a piece of candy with a brittle crust). So, the headline isn't really news at all.
The new part is the establishment and growth of such an obvious fissure where one did not exist before. The new one is fascinating, but only the latest example of a process that has been ongoing for a long time, and which will probably continue for millions of years more before the ocean eventually invades.
So let me get this straight. There was an earthquake that opened a crack in the earth three months ago and now the scientists involved can tell, after only three months that there will be a sustained widening of this crack by less than one inch per year. After one million years of this exact widening of one inch a year there will be a new ocean created.
Maybe it is hjust me but most real scientific fact going out a million years would likely be based on more than a three month snapshot of data.
The Afar area is a triple junction where upwelling magma is driving 3 continental crust apart - the Arabian plate, West Africa and East Africa. The plates crack in 120 deg pieces because the configuration relieves plate extensional stress with minimal displacement. What typically happens when the basin expands is that one of arms is abandoned, again for thermodynamic reasons. Spreading along a single great circle requires less membrane deformation of the outer crust than spreading along 3. The principle of least action at work. In this case the active arms of the triple junction are the Red Sea and the East Indian ocean which are sites of rapid spreading of oceanic crust. Th East Africa Rift is clearly spread more slowly than the active arms and will fail. The North Sea, Mississipi delta, Camaroon rift, Connecticut Valley, etc are examples of rift valleys and failed arm abandonment during the opening of ocean basins. Sure, volcanism and rifting can still occur in the failed arm. The extensional faults that define these areas assures this. We see this in Afar, and deeper in the African rift. Camaroon is another example. The triple function there opened 120 Mya and it is still active. But is will never form a wide ocean basin. Afar tectonics are still a very interesting phenomen.
an ill wind that blows no good
The fissure grows 8 meters wide in 3 weeks following an earthquake on Sept 14, and then increases at a rate of about 0.8 inches per year. Given the first metric is even possible, it's absurd to think that the the second rate will remain constant so projection to millions of years is invalid. It would be just as valid to conclude that the increase is decelerating and eventually close back up.
I wonder if this event will help provide some clue as to what is driving the plate motions.
When I last had lectures in a subject that had to do with plate-tectonics (~1 year ago) there still wasn't any theory that could "give" enough force to create the plate motions that are observed today and should have happened in the past (at least to the knowledge of my professor).
For example India should have stopped it's northwards motion long ago but it is still not moving it's way northwards into Eurasia.
One man's Troll is the other man's Funny and is the third man's Truth.
You can't handle the truth.
http://www.volcano.si.edu/world/volcano.cfm?vnum=0 201-113&volpage=var
Speaking as an amateur geologist, I think I can safely use the geophysical jargon and say, "MAN that is FREAKY!"