Revealed: How Earth Got Tectonic Plates

[Dem!god]

Geophysicists have discovered that earth's outermost layer, or lithosphere, was weakened by movement in viscous layers below it - a process when one plate dives below another.



Starting roughly four billion years ago, cooler parts of earth's crust were pulled downwards into the warmer upper mantle, damaging and weakening the surrounding crust. The process happened again and again until the weak areas formed plate boundaries.



"Over a much longer period, the same process could have created many tectonic plates. We have got a physical mechanism to explain how it could have happened," study author David Bercovici from Yale University explained.



The process began about four billion years ago and caused complete fractures some three billion years ago. To investigate how the plates formed, Bercovici and Yanick Ricard of University of Lyon in France developed a computer model of earth's crust as it may have existed billions of years ago.



The model included a low-pressure zone at the base of the crust which caused a piece of the crust to sink into the upper mantle - mimicking conditions thought to have occurred early in the earth's history. As the process repeated over time, it created a large tectonic plate with an active subduction zone.



Prior studies suggested the age of the plates - based on evidence of subduction gathered from minerals - preserved in ancient rocks. In geology, subduction is the process that takes place at convergent boundaries by which one tectonic plate moves under another tectonic plate and sinks into the mantle as the plates converge.



The oldest such specimens are four-billion-year-old zircons found in the Jack Hills of Australia that appear to have formed at temperatures and pressures that are indicative of subduction.



"The subsequent movement of the plates has erased much of the evidence of their origin," said Paul Tackley, a geophysicist at Swiss Federal Institute of Technology (ETH) in Zurich, Switzerland in a report published in Nature.



According to Robert Stern, a geologist at University of Texas in Dallas, there is no firm evidence of plate tectonics earlier than one billion years ago, but the new mechanism behind plate formation is "the first interesting example of how it might have occurred"


Revealed: How Earth Got Tectonic Plates | Science | www.indiatimes.com

@DRAY @thesolar65 @Parul @chak de INDIA @Indischer @levina @cheekybird @45'22' @M-48 and others......
http://www.indiatimes.com/technology/enterprise/samsung-to-open-4000-stores-across-india-140069.html

 

[Dubious]

Well honestly speaking we were thought the first 3 paragraphs in middle school...esp this part

" cooler parts of earth's crust were pulled downwards into the warmer upper mantle, damaging and weakening the surrounding crust. The process happened again and again until the weak areas formed plate boundaries. "

But I guess the process and origin was not explained properly back then

Ahh the keywords:

"the first interesting example of how it might have occurred"

 

[Indischer]

I wish plate tectonic shifts were a more rapid process. They'd be a perfect troll for mankind, altering National boundaries just when a war was waged to settle such a dispute.

 

[Dem!god]

Well honestly speaking we were thought the first 3 paragraphs in middle school...esp this part

" cooler parts of earth's crust were pulled downwards into the warmer upper mantle, damaging and weakening the surrounding crust. The process happened again and again until the weak areas formed plate boundaries. "

But I guess the process and origin was not explained properly back then

Ahh the keywords:

"the first interesting example of how it might have occurred"

hehehe....
what did u expected an article full of technical jargon.....
cooling and heating are simple phenomenon but have caused big changes on earth crust.....

]

 

[thesolar65]

I wish plate tectonic shifts were a more rapid process. They'd be a perfect troll for mankind, altering National boundaries just when a war was waged to settle such a dispute.

But then Earthquake, volcano and Tsunami would have been a regular occurrence and our very existence would be in doubt!!

 

[Indischer]

But then Earthquake, volcano and Tsunami would have been a regular occurrence and our very existence would be in doubt!!

All the better.

 

[Levina]

I wish plate tectonic shifts were a more rapid process. They'd be a perfect troll for mankind, altering National boundaries just when a war was waged to settle such a dispute.

Amen to that!!

 

[Missile]

So when these plates are going to settle down? Any idea lol

 

[Dem!god]

So when these plates are going to settle down? Any idea lol

never unless and until the the core of the earth starts to solidify and there is no more radioactive activity down the mantle....

 

[Missile]

never unless and until the the core of the earth starts to solidify and there is no more radioactive activity down the mantle....

Means end of this earth's life. So it is possible.

 

[OrionHunter]

Damn! And I thought the Earth was hollow!!!

 

[notsuperstitious]

I was always like ''How on earth did that happen?''

Ok sorry could not resists that!

BTW any idea if the pakistani plate is separating anytime soon and joining Saudi Arabia?

 

[Dem!god]

Means end of this earth's life. So it is possible.

yes...of course......nothing is there for eternity.....
life on earth can end in many ways......not only this...our sun will die one day, our solar system will be a black hole in times to come....
and the earth willl cool down for sure....as the radioactive substance will end up their cycle they will stop producing heat what they do now during their disintegration in mantle layer which is mainly responsible for tectonic plate movements........the heat at core is said to be there because of the pressure applied by the above lying layers....but slowly and slowly it will cool down....as it has cooled down and reached this stage.....

 

[dray]

I even heard that Bangladesh plate is slipping into the Bay of Bengal with all the biscuits & peanuts on it.
@BDforever

 

[BDforever]

I even heard that Bangladesh plate is slipping into the Bay of Bengal with all the biscuits & peanuts on it.
@BDforever