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Offline neilep

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What's the Asthenosphere ?
« on: 12/07/2008 22:05:17 »
Dear Oldies-but-goodies !

Here's the Earth !




See ?..I always knew it was flat !

*sheepy giggles*...lol...daughty tells me that Earth is round..*yeah right !!*..well..if it is round then we all know that it contains choccy milkshake just a few yards beneath the surface !

I can't dig that far deep but as a firm believer in empirical study I took a marble and placed it on the ground.....If the world was round it would have rolled yes ?..see ?..and it did not !!


Anyway...daughty also *guffaw guffaw chortle*...says that one of the layers is called the asthenosphere....LOL !!....she's such a silly girl....I am going to detain her in her room and take all her privileges away !

Anyway, if such a thing as the asthenosphere actually exists...can ewe tell me what it is ?

LOL.....

*sheepy goes off to administer a severe scolding to cheeky daught*



hugs and shmishes




Neil
Daughty Berater

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Offline rosalind dna

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What's the Asthenosphere ?
« Reply #1 on: 13/07/2008 00:02:25 »
Neil that daughter of yours, it seems was talking some good sense to you as wiki says also:


The asthenosphere (from an invented Greek ἀσθενός a + ''sthenos "without strength" and greek word σφαίρα (sphera) meaning globe) is the region of the Earth between 100 and 200 km (~ 62 and 124 miles) below the surface but perhaps extending as deep as 400 km (~ 249 miles) that is the weak or "soft" zone in the upper mantle. It lies just below the lithosphere, which is involved in plate movements and isostatic adjustments. In spite of its heat, pressures keep it plastic, and it has a relatively low density. Seismic waves, the speed of which decrease with decreasing rigidity of a medium, pass relatively slowly through the asthenosphere, the cue that originally alerted seismologists to its presence; thus it has been given the name low-velocity zone.


Under the thin oceanic plates the asthenosphere is usually much nearer the seafloor surface, and at mid-ocean ridges it rises to within a few kilometres of the ocean floor.

The upper part of the asthenosphere is believed to be the zone upon which the great rigid and brittle lithospheric plates of the Earth's crust move about. Due to the temperature and pressure conditions in the asthenosphere, rock becomes ductile, moving at rates of deformation measured in cm/yr over lineal distances eventually measuring thousands of kilometers. In this way, it flows like a convection current, radiating heat outward from the Earth's interior. Above the asthenosphere, at the same rate of deformation, rock behaves elastically and, being brittle, can break, causing faults. The rigid lithosphere is thought to "float" or move about on the slowly flowing asthenosphere, creating the movement of crustal plates described by Plate tectonics theory.

Although its presence was suspected as early as 1926, the worldwide occurrence of the asthenosphere was confirmed by analyses of earthquake waves from the Great Chilean Earthquake of May 22, 1960.

http://en.wikipedia.org/wiki/Asthenosphere
 

Offline neilep

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What's the Asthenosphere ?
« Reply #2 on: 13/07/2008 19:16:35 »
What ?....Oh Nooooooooooo !!!

*le sulk*.....THANK EWE Rosalind dna

So, not only is daughty right about the Earth being round, she is also right about the asthenosphere !!...great !!


Now I have to say sorry and revoke her privileges....

Wonderful information Rosalind..Thank EWE !

« Last Edit: 13/07/2008 19:20:02 by neilep »
 

Offline DoctorBeaver

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What's the Asthenosphere ?
« Reply #3 on: 13/07/2008 21:34:38 »


The Earth is an M&M!  [:0]
 

Offline neilep

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What's the Asthenosphere ?
« Reply #4 on: 13/07/2008 21:45:40 »


The Earth is an M&M!  [:0]

Excellentay !!..so, I was nearly right about the choccy stuff !

 

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What's the Asthenosphere ?
« Reply #4 on: 13/07/2008 21:45:40 »

 

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