The earth will end – in 10 million years! I think!

[GreatLich]

why is there an assumption that the earth will be destroyed if/when its core/mantel were to cool down?

Haven't you seen The Core?!
Laserbeams from space is what will happen, man!

 

[Netheralian]

Awesome, so essentially the sun will toast us with its red giant before the Earth's own heat dies.

It would appear so - for the core at least...

 

[Womble]

Awesome, so essentially the sun will toast us with its red giant before the Earth's own heat dies.

It would appear so - for the core at least...

Awesome

I think i had heard something along those lines before but didn't want to say it as it was a fairly elusive memory.

 

[scalyblue]

why is there an assumption that the earth will be destroyed if/when its core/mantel were to cool down?

Haven't you seen The Core?!
Laserbeams from space is what will happen, man!

At least the consulting team convinced the directors to not have WINDOWS on the ship.

 

[orpiment99]

Wait, wasn't The Core a comedy?

Womble, you must admit that geology majors spend an unfortunate amount of time coloring between the lines.

First off, the easiest way to visualize the mantle is to think of it like a sponge. Soft, malleable, but solid material that has pockets of liquid (melt).

Secondly, oil (and please tell me you're not thinking of it like a lake down there in some void) is less dense than the surrounding rock (at relatively low pressures in the crust) and attempts to migrate to where the pressure is less (upward).

As far as oil maturation, here is a fairly good explanation:
http://www.kingdomdrilling.co.uk/diggin/Oil%20and%20gas%20maturation%20688.pdf

Basically, above 260 degrees C, any organic material is destroyed.

 

[GreatLich]

Haven't you seen The Core?!
Laserbeams from space is what will happen, man!

At least the consulting team convinced the directors to not have WINDOWS on the ship.

Actually, I think adding Driver Hell to the scene with the nuclear reactor would've been appropriate.

 

[Tsunamie]

..... I. Am. A. Geologist. I know what i'm talking about on this one.

Milgram experiment anyone -
I am simply asking for an explanation to a field I can understand. What you stating contradicts all the material I have seen so far. So asking for more information was not that unreasonable.

But anyway, this that i am going to use to back this up....
P wave and S wave velocities - These dip down a bit in the asthenosphere with the 5% melt but then they rocket up as the go deeper into the mantle. The S waves bomb out at the Guttenburg discontinuity (core-mantle boundary) as the outer core is molten. The fact that the body waves speed up is indicative of the mantle being solid. The mantle IS solid, but because of the intense heat and pressure (the core of the planet if hotter than the surface of the sun) and as a result of this over geological time it convects and behaves like a liquid. The Atlantic ocean is growing at about the same rate human finger nails grow.

Do you mean the material itself is in a solid state? However the environment forces it in to granular formation to act like sand, where the grains are smaller?
As that's how I understand your explanation. You also justify it by observations of wave refraction?

It was as far from a hypothysis, in fact so far as to be a highly misinformed ramble. I did read your first post, and when I did it was almost like one of those cartoon moments when the eyes come out on stalks"¦..i even yelled some manner of abuse at my laptop at reading it, so I'm taking it easy whilst posting.

Actually, the hypothesis that the earth is cooling and that we are decreasing the length at which the planets core temperature to support life is quiet valid. Even if the length is small and past the red giant phase of the sun. That is irrelevant to what I was trying to calculate.

As for your loony notion of us drilling to the core let me correct you on that creotard level fallacy. The furthest we have ever drilled has been a few km (I can't remember exactly off the top of my head and if you really want to know you can google it yourself), we've not even scratched the surface in terms of drilling, the geothermal gradient is quite steep you see"¦.there's all this heat down there that will last for a few more billion years.

Okay, now I am confused? What is this about drilling? I have to my knowledge not made any statements about drilling.
I gathered that there is enough heat for several billion years. However, I was hoping to find how long that is rather then say a few billion more years.

And besides, I'm being witty and creatively inventive with my insults, grow a spine"¦

[/quote]
I have one thanks. I am just pointing out how arrogant you are.

oooOOOooo"¦"¦.who's making the assumptions now?? I made NO assumptions about your knowledge other than you having a huge howling gap"¦. And don't go making assumptions about what goes on in a classroom, because I'll own you on that front too. And regardless of what you think is productive or helpful it is at least entertaining for myself and a few others.

That's kind of what I am driving at. I was pointing out that that gap is caused from the fact that I have not studied in this field as you have for most of my life. Where the last time I was taught anything about geology was at GCSE level.
My assertion was that your expectation of everyone knowing the world's core temperature is powered by radioactive decay is unrealistic given the current education specifications.

http://www.amazon.co.uk/Geoscience-Understanding-Geological-Dee-Edwards/dp/0340688432/ref=sr_1_2?ie=UTF8&s=books&qid=1255711765&sr=1-2
pwnage"¦

http://www.amazon.co.uk/Understanding-Geology-Pupils-Work-Book/dp/0050036645/ref=sr_1_1?ie=UTF8&s=books&qid=1255711795&sr=8-1
double pwnage"¦.

http://www.amazon.co.uk/Geological-Science-Andrew-Mcleish/dp/0174482213/ref=sr_1_1?ie=UTF8&s=books&qid=1255721538&sr=1-1
and for shits and giggles triple pwnage"¦..

There must be something wrong with your brain. Since I asked you to provide evidence that it was taught at GCSE level. Yet the books review and other guidelines clearly state these books are all for A level courses in Geography or earth sciences.
I asked you to provide books that explained radioactive decay for 16 year olds at GCSE level because that would have been the most reasonable age. Unless you take a specialist course in the subject. Which I already pointed out to you.
Since the reference was made to as thought I had wasted tax payers money, the only age rage that that could have happened is between the age of primary school and the end of secondary school. Which you have yet to prove.
So the 3 points you racked up were discounted because of fouls. ! Point to me for pointing out your obvious mistakes.

Now it's been a while since I read that level of text in detail but I certainly remember covering the fact that radio active decay produced the heat that kept the earth going in my a-level. And whilst I've not studied the WJEC's GCSE spec in detail but I'm sure it's there. Oh and I doubt that GCSE Geography will cover it as that's a humanities subject, and you see Geology just happens to be a science. So these books won't be used for teaching Geography (as that's just colouring in) but they will in a Geology lesson.

YOU WOULD HAVE COVERED IT IN A GEOGRAFY CLASS AT A LEVELS. You books already pointed that out. Unfortunately not everyone decided to study geography at A level.
http://www.wjec.co.uk/uploads/publications/8053.pdf
The teachers guide to geography at GCSE level does not include the study of how the core creates and generates heat. I therefore make the assertion that this material would not have been taught 8 years ago either. Which is when I studying at this level.
Which kind of re-inforces the point that you were being unreasonable in expecting a level of knowledge that is taught at a specialist course level.

The best bit is the fact I'm a teacher, so I know what goes on in schools, and I just happened to go to the only place that does ITT for people that have Geology as their science specialism.

So essentially you're a teacher at a specialist school. Wow, does that cover the fact that the national guidelines don't seem to cover this topic in the age range I specified. Does it change the fact that at College level (A Levels) There are hundreds of courses and that specific knowledge you keep harping on about is only taught at this level in the UK?
You don't seem to be a very competent teaches in this case if you don't even know what level your subject is taught at.

Awww"¦"¦.bless"¦..you know I find your lack of initial research disturbing. {10 Womble points to whoeer gets that paraphrased quote}

Which only shows how immature you actually are.
Netheralian,
So when would be the expected date the tectonic plates fuse? Apart of my argument is that environments that produce huge amounts of heat with several chemicals being pushed together to form basic blocks for life are at volcanic location. If these environments disappear, then would it not be safe to assume that a decrease in probable new life will disappear and bio-diversity will take a hit?
As more advanced creatures die out and only mutate based on the survivor. I was thinking of bio-diversity in the beginning of life. I obviously assume that RNA and DNA are being created by natural process now in these environments.
scalyblue, My hypothesis does not really bet on the planet not sustain life after the surface temperature goes down as the core cools. My hypothesis drives at our survival rating going down because of the lack of diversity provided by the environments such as gisers or underwater jet streams that are thought to be the environments the first life on this planet was generated from.
I also still am trying to work out if basic life can live in an environment where the surface temperature is entirely dependent on the sun for heat.

 

[kf00kaha]

Milgram experiment anyone -
I am simply asking for an explanation to a field I can understand. What you stating contradicts all the material I have seen so far. So asking for more information was not that unreasonable.

Maybe not, but it might be easier to tell if you state your sources of information (or some of the most relevant at least).

Do you mean the material itself is in a solid state? However the environment forces it in to granular formation to act like sand, where the grains are smaller?
As that's how I understand your explanation. You also justify it by observations of wave refraction?

No, the material is solid but not granular, more like viscous. Due to the temperature and pressures it get some strange properties. I suggest a chemistry book or possibly a material physics book. Or a geology book...
Wave refraction is a known technique to measure the structure of the earth.

Actually, the hypothesis that the earth is cooling and that we are decreasing the length at which the planets core temperature to support life is quiet valid. Even if the length is small and past the red giant phase of the sun. That is irrelevant to what I was trying to calculate.

If you look at my first post you see pretty quickly that it will effect the age of the earth with a very unsignificant amount of time. But as stated earlier in the thread, the oil will migrate upwards with time, and the tectonic plates doesn't move very fast.

I gathered that there is enough heat for several billion years. However, I was hoping to find how long that is rather then say a few billion more years.

Then it's time to head to the library and read up. If you want to understand this it will take us more time to provide you the info, than you reading up on your own.

Netheralian,
So when would be the expected date the tectonic plates fuse? Apart of my argument is that environments that produce huge amounts of heat with several chemicals being pushed together to form basic blocks for life are at volcanic location. If these environments disappear, then would it not be safe to assume that a decrease in probable new life will disappear and bio-diversity will take a hit?
As more advanced creatures die out and only mutate based on the survivor. I was thinking of bio-diversity in the beginning of life. I obviously assume that RNA and DNA are being created by natural process now in these environments.
scalyblue, My hypothesis does not really bet on the planet not sustain life after the surface temperature goes down as the core cools. My hypothesis drives at our survival rating going down because of the lack of diversity provided by the environments such as gisers or underwater jet streams that are thought to be the environments the first life on this planet was generated from.
I also still am trying to work out if basic life can live in an environment where the surface temperature is entirely dependent on the sun for heat.

Now, this is a bit interesting: you assume that abiogenesis is responsible for sustaining life/biodiversity on earth? Considering that, to my knowledge, scientist have not yet been able to observe abiogenesis, that's a quite shaky hypothesis, I would say about as shaky as your first one. If abiogenesis was responsible for sustaining life on earth, don't you think this phenomena would have been observed? I'd say evolution is quite enough to sustain the biodiversity, but it will not be the same as today. Aye laddie! Set course for the library! And use your critical thinking also on your hypotheses: if you know you're ill-informed you're most likely wrong in some way...

 

[Womble]

..... I. Am. A. Geologist. I know what i'm talking about on this one.

Milgram experiment anyone -
I am simply asking for an explanation to a field I can understand. What you stating contradicts all the material I have seen so far. So asking for more information was not that unreasonable.

Miligram is a non-sequiter, I'm not asking you to obey me I'm stating my qualification and area of expertise. The correct criticism would have been to point out a claim to authority. {point to me}

Fine, pony up the stuff you've read and I'll get to verifying if your stuff is decent or if its twoddle. You've been provided with information, admittedly you've had flak but then your opening post did contain the academic equivalent of arse gravy.

But anyway, this that i am going to use to back this up....
P wave and S wave velocities - These dip down a bit in the asthenosphere with the 5% melt but then they rocket up as the go deeper into the mantle. The S waves bomb out at the Guttenburg discontinuity (core-mantle boundary) as the outer core is molten. The fact that the body waves speed up is indicative of the mantle being solid. The mantle IS solid, but because of the intense heat and pressure (the core of the planet if hotter than the surface of the sun) and as a result of this over geological time it convects and behaves like a liquid. The Atlantic ocean is growing at about the same rate human finger nails grow.

Do you mean the material itself is in a solid state? However the environment forces it in to granular formation to act like sand, where the grains are smaller?
As that's how I understand your explanation. You also justify it by observations of wave refraction?

As has been said, and I'll say it again, the Mantle is solid, due to the intense heat and pressure there is some funky stuff going on in there. I've been having trouble trying to remember the name given to the consistency of the Mantle but I've been coming up with a blank, hence I've not mentioned this. I think the term is plasma that's used but I'm really not convinced. And my explanation has nothing to do with sand, I mention the states of solid and liquid and I've gone with the very simplified version of how the waves travel through the earth. What do you want me to do, spoon feed you the information??

It was as far from a hypothysis, in fact so far as to be a highly misinformed ramble. I did read your first post, and when I did it was almost like one of those cartoon moments when the eyes come out on stalks"¦..i even yelled some manner of abuse at my laptop at reading it, so I'm taking it easy whilst posting.

Actually, the hypothesis that the earth is cooling and that we are decreasing the length at which the planets core temperature to support life is quiet valid. Even if the length is small and past the red giant phase of the sun. That is irrelevant to what I was trying to calculate.

That first sentence was poorly constructed, although I think I've worked out what you are trying to say. And no, we don't have the ability to cool the planet in any way as to cause issues for its ability to support life. Shitting up the atmosphere the way we are is having an impact though, but that's not what we're talking about. The planets internal heat is not going to give up any time soon, this was addressed in the post of another member earlier on.

As for your loony notion of us drilling to the core let me correct you on that creotard level fallacy. The furthest we have ever drilled has been a few km (I can't remember exactly off the top of my head and if you really want to know you can google it yourself), we've not even scratched the surface in terms of drilling, the geothermal gradient is quite steep you see"¦.there's all this heat down there that will last for a few more billion years.

Okay, now I am confused? What is this about drilling? I have to my knowledge not made any statements about drilling.
I gathered that there is enough heat for several billion years. However, I was hoping to find how long that is rather then say a few billion more years.

You're the one that came out with the delight of saying that we're over extracting fossil fuels and that what if we take all out and there's not enough to keep the core going or some such. I was mearly pointing out how we've bearly scratched the surface of the planet, the core is 6000km away to round it off. Am I not allowed to give you some context and background info? Earlier you were whinging about not being told anything, make your mind up.

And besides, I'm being witty and creatively inventive with my insults, grow a spine"¦

I have one thanks. I am just pointing out how arrogant you are.

Pfft"¦..I actually couldn't be less arrogant without getting up early in the morning to practice. Whilst I can be cocky from time to time arrogance isn't something I do. Besides, this would be filed under ad hominim

oooOOOooo"¦"¦.who's making the assumptions now?? I made NO assumptions about your knowledge other than you having a huge howling gap"¦. And don't go making assumptions about what goes on in a classroom, because I'll own you on that front too. And regardless of what you think is productive or helpful it is at least entertaining for myself and a few others.

That's kind of what I am driving at. I was pointing out that that gap is caused from the fact that I have not studied in this field as you have for most of my life. Where the last time I was taught anything about geology was at GCSE level.
My assertion was that your expectation of everyone knowing the world's core temperature is powered by radioactive decay is unrealistic given the current education specifications.

I haven't studied anything for most of your life, so I don't know what you're on about. Another example of a poorly constructed sentence, a point actually that I'll come back to later after a little doosey you've dropped.

I will say this again, and I will say it with added emphasis"¦. I. Have. Not. Made. Any. Assumptions. About. Your. Knowledge"¦..aside from the lack thereof. And I'm fully aware of the current curriculums and National Curriculum, and you appear to be making a faulty assumption that the curriculum is static. Which it isn't, and if I'm correct then I get another point, again I'll refer to why in a bit. {2 points to me}

http://www.amazon.co.uk/Geoscience-Understanding-Geological-Dee-Edwards/dp/0340688432/ref=sr_1_2?ie=UTF8&s=books&qid=1255711765&sr=1-2
pwnage"¦

http://www.amazon.co.uk/Understanding-Geology-Pupils-Work-Book/dp/0050036645/ref=sr_1_1?ie=UTF8&s=books&qid=1255711795&sr=8-1
double pwnage"¦.

http://www.amazon.co.uk/Geological-Science-Andrew-Mcleish/dp/0174482213/ref=sr_1_1?ie=UTF8&s=books&qid=1255721538&sr=1-1
and for shits and giggles triple pwnage"¦..

There must be something wrong with your brain. Since I asked you to provide evidence that it was taught at GCSE level. Yet the books review and other guidelines clearly state these books are all for A level courses in Geography or earth sciences.
I asked you to provide books that explained radioactive decay for 16 year olds at GCSE level because that would have been the most reasonable age. Unless you take a specialist course in the subject. Which I already pointed out to you.
Since the reference was made to as thought I had wasted tax payers money, the only age rage that that could have happened is between the age of primary school and the end of secondary school. Which you have yet to prove.
So the 3 points you racked up were discounted because of fouls. ! Point to me for pointing out your obvious mistakes.

OOOOoooooohhhh! Something wrong with my brain eh? Really, are you sure you absolutely want to go down that route with me? Well you've written it so I guess you must do, in which case my gloves are going to come off for a while spud brain.

As it happens I am dyslexic, so some might say that something is wrong with my brain, however they'd be quite wrong in fact. Whilst my brain does work differently and I might have some comprehension issues I put the effort in to make sure I've understood things, like taking my time to re-read stuff. Maybe you should too.

Just because the reviews say that they're for A-Level doesn't mean that they can't be used for other levels, I know I certainly would use them and just be selective. And those books are used, and not just in A-Level they are used in GCSE Geology as they are actually about the only text books available at those levels. How about you ignore the reviews and listen to the person that is telling you what they'd use, also I'm fully aware of limitations in the curriculum but that doesn't mean that these things aren't available.

You know I don't need to prove anything to you, so far you've proven to be dogmatic in your hold on things that are incorrect. Those books are used in schools to teach Geology at A-Level and GCSE, just because you didn't get the chance isn't something to whinge to me about. If you've identified a whole in your knowledge then it's up to you to do something about it or not, however whinging is only going to lead to people disliking you.

Since you've been counting point I've counted a few myself, I've scored 2 so far and you as for those alleged 'obvious mistakes' I made the egg is in fact you your face not mine as those books are used. Yes I've just repeated myself but I'm actually starting to think that repeating myself will be the only way you will start to get the message.

*crackles knuckles*

Right, lets take on the rest of your ramblings"¦.

Now it's been a while since I read that level of text in detail but I certainly remember covering the fact that radio active decay produced the heat that kept the earth going in my a-level. And whilst I've not studied the WJEC's GCSE spec in detail but I'm sure it's there. Oh and I doubt that GCSE Geography will cover it as that's a humanities subject, and you see Geology just happens to be a science. So these books won't be used for teaching Geography (as that's just colouring in) but they will in a Geology lesson.

YOU WOULD HAVE COVERED IT IN A GEOGRAFY CLASS AT A LEVELS. You books already pointed that out. Unfortunately not everyone decided to study geography at A level.
http://www.wjec.co.uk/uploads/publications/8053.pdf
The teachers guide to geography at GCSE level does not include the study of how the core creates and generates heat. I therefore make the assertion that this material would not have been taught 8 years ago either. Which is when I studying at this level.
Which kind of re-inforces the point that you were being unreasonable in expecting a level of knowledge that is taught at a specialist course level.

No spud brain, Geology is where I covered it. You see Geology is the study of the earth (it's in the name), geo, earth, ology, study of. I didn't do A-Level geography as to be quite frank the human crap bores the tits off me. As is dealing with the ramblines your coming it with. SEE I CAN USE CAPS LOCK TOO. You know last night when reading this for the first time I was spitting feathers at your lack of knowledge, now I almost don't care. But I digress"¦.

You can't go looking in a geography spec for something from Geology. FFS! Geology/Geography"¦..even if you don't get the spelling differences one is clearly longer than the other! This level of logic seems to be on a par with some creationist levels of stupidity. Geography deals with people and places and yes it has some overlap with Geology but that's only in so far as they both cover SURFACE processes (surface is in caps for emphasis). Geography deals with the interior of the earth as your average shelf stacker in tescos deals with food production"¦.i.e. they don't. Geology does deal with the interior of the earth so you can't even seem to research properly. And don't whinge to me about not getting the opportunity to find these things out. Your using the internet for petes sake, wiki it or something and stop being a muppet, do some independent learning.

The best bit is the fact I'm a teacher, so I know what goes on in schools, and I just happened to go to the only place that does ITT for people that have Geology as their science specialism.

So essentially you're a teacher at a specialist school. Wow, does that cover the fact that the national guidelines don't seem to cover this topic in the age range I specified. Does it change the fact that at College level (A Levels) There are hundreds of courses and that specific knowledge you keep harping on about is only taught at this level in the UK?
You don't seem to be a very competent teaches in this case if you don't even know what level your subject is taught at.

Yes the school I'm at has specialist status, but it's in the arts"¦.and to be fair I don't think you'd have even a clue as to how the specialist status of schools works.

The national curriculum now expects kids to be taught how science works, with the emphasis on scientific method and processes etc and the subject knowledge being the means. So any decent science teacher that knows some earth science can fit it in. Colleges do more than a-levels and a-levels aren't just taught at colleges.

I'm a competent teacher, you just don't know what the smeg you are talking about. I do, I've done the course and got the qualification and the certificates to prove it. Part of becoming a teacher is taking in the levels and options for qualifications in the field you teach"¦"¦so in the points system I'm on 6 now.

Awww"¦"¦.bless"¦..you know I find your lack of initial research disturbing. {10 Womble points to whoeer gets that paraphrased quote}

Which only shows how immature you actually are.

No, it's not immature, you come to a forum like this and expect a loving reception for posting absolute drivel? Come on, if I went somewhere and posted as much rubbish as you did in that first post I'd take it on the chin if I got slated. And if you think your being hard done by with this treatment then thank whatever you like you've never seen some of the forums I have"¦"¦I've been to places where they aren't satisfied until you've near enough been beaten into the ground and the treatment you've received here would be akin to a lovers caress there. So again, grow a spine. Stop whinging and do some research.

{10 Womble points go to BenQ}

Netheralian,
So when would be the expected date the tectonic plates fuse?

They'll fuse, split again and fuse, followed by more splitting and more fusing many time between now and the day the sun whacks the earth. How about you go do some research on projected plate movements"¦.

Apart of my argument is that environments that produce huge amounts of heat with several chemicals being pushed together to form basic blocks for life are at volcanic location.

I've read this through several times and I don't think theres anyway to interpret this other than"¦.wtf?

If these environments disappear, then would it not be safe to assume that a decrease in probable new life will disappear and bio-diversity will take a hit?

No.

As more advanced creatures die out and only mutate based on the survivor.

wtf?

I was thinking of bio-diversity in the beginning of life.

Nooo"¦"¦ First we got the life (however that happened), then the biodiversity kicked in later.

I obviously assume that RNA and DNA are being created by natural process now in these environments.

Yeah, it's called cells and cell division.

scalyblue, My hypothesis does not really bet on the planet not sustain life after the surface temperature goes down as the core cools.

ugh"¦ Double negative much. You've contradicted yourself. Until you write something that is tangled up then people won't be able to make sence of it.

My hypothesis drives at our survival rating going down because of the lack of diversity provided by the environments such as gisers or underwater jet streams that are thought to be the environments the first life on this planet was generated from.

No. Our survival will go down because by polluting our atmosphere we've essentially been crapping in our own backgarden. Gysers and the Black Smokers/Hydrothermal Vents will still be going long past our extinction. Hell they've been going probably since not long after we started to get surface water, however that is an assumption based on some study. It could be right it could be wrong, I'm not sure and at the moment I don't have the time to chase down any dates for the earliest examples.

Also again, this isn't a hypothysis, this is a wild guess at your lack of understanding"¦"¦I'd be doing the same if I tried coming up with a random guess about something to do with astronomy, and if I was I would expect AndromedasWake to take me down a few pegs for it.

I also still am trying to work out if basic life can live in an environment where the surface temperature is entirely dependent on the sun for heat.

"¦"¦

Do
Some
Research
!!!!

 

[GrolschMan]

Oh yea!

<BenQ dances on the spot>

I got 10 Womble points!
I got 10 Womble points!

To everyone else: YOU SHOULD HAVE TRIED HARDER!

 

[scalyblue]

I've heard the consistency of the mantle of the earth described as 'plastic' by smarter people than I. I've also heard the quite sensible description that the crust is what we get from the mantle melting

@OP, when somebody who reads and comprehends wikipedia's geology topics can have a better grasp of these subjects than you presented, there's a problem with your research.

 

[orpiment99]

I am simply asking for an explanation to a field I can understand.

There are several problems here, frankly. I'm just going to address this: it is difficult enough to try and distill several years of education into a simplified answer. When you are asking questions that you could reasonably have found the answers yourself, it makes things frustrating and more difficult on those of us who do have an education in the subject. An intelligent approach would have been to find the answers that you could and then ask your questions. Or even ask others where to look up the information for yourself.

 

[Womble]

I've heard the consistency of the mantle of the earth described as 'plastic' by smarter people than I. I've also heard the quite sensible description that the crust is what we get from the mantle melting.

Essentially yes. The crust can better be described as the scum of the earth, particularly the Continental crust. It's all the light stuff that won't subduct back into the mantle when Oceanic plates subduct.

 

[aeroeng314]

So in doing a bit of reading on Wikipedia about the Earth's mantle, I get the idea that its phase lies in some kind of strange intermediate between solid and liquid, but closer to solid. What I gather is that the flow of the mantle isn't like a conventional fluid flow where the stresses are related to shear rates but are related to actual plastic deformation of the solid itself. So, am I correct in my understanding that it's a solid under conditions which cause it to exhibit some fluid-like properties?

 

[Womble]

So in doing a bit of reading on Wikipedia about the Earth's mantle, I get the idea that its phase lies in some kind of strange intermediate between solid and liquid, but closer to solid. What I gather is that the flow of the mantle isn't like a conventional fluid flow where the stresses are related to shear rates but are related to actual plastic deformation of the solid itself. So, am I correct in my understanding that it's a solid under conditions which cause it to exhibit some fluid-like properties?

Sounds like you've got it. It's a bit of a mind bender at first but it's not so hard once you get used to it.

 

[kf00kaha]

So in doing a bit of reading on Wikipedia about the Earth's mantle, I get the idea that its phase lies in some kind of strange intermediate between solid and liquid, but closer to solid. What I gather is that the flow of the mantle isn't like a conventional fluid flow where the stresses are related to shear rates but are related to actual plastic deformation of the solid itself. So, am I correct in my understanding that it's a solid under conditions which cause it to exhibit some fluid-like properties?

Sounds like you've got it. It's a bit of a mind bender at first but it's not so hard once you get used to it.

Wikipedia has a pretty comprehensive (and quite short ) description of non-Newtonian fluids (i.e. fluids that don't behave like water). This could help a bit to understand the above subject.

Also I could point out that plasma is not a good word, since this is when the electrons in a gas get excited enough to break free from the nucleus and move freely in the gas (ionic gas).

 

[Womble]

Sounds like you've got it. It's a bit of a mind bender at first but it's not so hard once you get used to it.

Wikipedia has a pretty comprehensive (and quite short ) description of non-Newtonian fluids (i.e. fluids that don't behave like water). This could help a bit to understand the above subject.

Also I could point out that plasma is not a good word, since this is when the electrons in a gas get excited enough to break free from the nucleus and move freely in the gas (ionic gas).

Like i said i was reluctant at calling it a Plasma as i didn't think it was the right word, and i am aware of it's use for a super charged gas. Thanks for the link though and i'll check it out

 

[borrofburi]

So in doing a bit of reading on Wikipedia about the Earth's mantle, I get the idea that its phase lies in some kind of strange intermediate between solid and liquid, but closer to solid. What I gather is that the flow of the mantle isn't like a conventional fluid flow where the stresses are related to shear rates but are related to actual plastic deformation of the solid itself. So, am I correct in my understanding that it's a solid under conditions which cause it to exhibit some fluid-like properties?

Reminding of the nightmares of classes on fluid dynamics and materials...

 

[kf00kaha]

Reminding of the nightmares of classes on fluid dynamics and materials...

Oh yeah *shudder*

Reynolds and Navier-Stokes still wake me up screaming sometimes :cry: :ugeek: