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Author Topic:   center of the earth
simple 
Inactive Member


Message 256 of 310 (183428)
02-06-2005 4:48 AM
Reply to: Message 253 by DrJones*
02-06-2005 3:53 AM


Re: cool suspects.
quote:
As it has been pointed out multiple times the evidence does not support a cool core
I disagree. Maybe I just am not educated enough to get where someone actually nailed it. Look at percys 4 points!
Now I don't have any idea what the temperature is in the earth, of course. So I can't say it is cool. Therefore I can't prove something I don't know. What I try to do here is see if we can prove it is hot. Then, all need for orher speckulation disappears.
Seems to me, if someone had a good case, like that the core was hot, that they should be able to present it. If they can't then I'll worry about considering whether some cooler model can be better matched to the evidence.
All I'm trying to do is see if we have evidence for the heat claimed so so widely. I do not (yet) claim it is cool!! If I played the devil's advocate here, and took the cool side, it was only for the sake of exploring how strong the evidence is, when we get right down to it.

This message is a reply to:
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Replies to this message:
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simple 
Inactive Member


Message 257 of 310 (183433)
02-06-2005 5:25 AM
Reply to: Message 246 by wmscott
01-31-2005 5:32 PM


Re: Before taking off on flights of fancy, check the evidence and do the math,
quote:
At the exact center of the earth, the pull of gravity is balanced and you would be weightless. So you are correct on the idea of being able to balance a lighter object in the center of the planet. The problem is the instability, the slightest wobble and the balance would be lost
Well I have a few ideas on this, but this thread isn't the place for them. Now, I just want to satisfy the basic density and specific gravity requirements, and leave the fancy stuff. So, say the core is a cool dense solid, surrounded by liquid. Aside from the gyro, another topic in itself, why must it be hot?
quote:
So I guess you could have a cold iron core surrounded by the molten outer core, but I don't see any point to it, since the outer core would over time heat the inner core.
In other words, wheter it is gold, or whatever, long as it's solid, and matches the density.? With water as an outer core, and a few other tweaks, I still say, given the young earth age scenario, why hot? Now as far as the 'slightest wobble' goes, I think I read where the magnetic field is thought to help support the core, sort of. If you've seen a beech ball at the end of a hose blowing air, it is suspended in the air on top of the hose. Could, with magnetic field, and a pressure so great, and density difference in inner and outer core help give a little of a similar type effect?
quote:
I see some of the other posters have posted the density figures for inside the earth, those figures are from the travel speeds of the P waves through the earth
I spent some time on another forum, so can hardly remember the humble beginnings here, and where we were. Anyhow, there is a 'travel time' for the core, I think about 4 seconds. Overall, we know the density, and travel time. But that may allow some things that would still work very well, in a cooler model.
quote:
No, it wouldn't, the low density would show up very clearly, the high travel speeds of the P waves in the core show a much higher density. Gold would have to be very hot to be liquid
Yes, thanks. I have moved on quite a bit since that silly little thought!
quote:
The density is known by the P wave speed, that it is mostly iron is indicated by other clues like the magnetic field and the relative abundance of elements in the universe
Wow! I like that! The rest is a piece of cake, what is left on the thread is the waves. Here, you indicate it was density that is the clincher. Great. Same thing I arrived at on the other forum.
quote:
What on earth do you mean? You aren't making any sense, stop and think about it for a moment. If you are talking about the flood waters coming from inside the earth, and they are hot, in flooding the surface they would heat the surface. If you are talking about a sudden movement of the earth's plates, heat coming up suddenly wouldn't do it, you would have to slowly heat the surface from below so it could flow
I was thinking the friction from continents moving would have been the big thing. But, if it can be proved the erth center is hot, that would be a moot point, because water couldn't have been down there.

This message is a reply to:
 Message 246 by wmscott, posted 01-31-2005 5:32 PM wmscott has not replied

JonF
Member (Idle past 246 days)
Posts: 6174
Joined: 06-23-2003


Message 258 of 310 (183462)
02-06-2005 8:49 AM
Reply to: Message 251 by simple
02-06-2005 3:35 AM


Re: cool suspects.
Nothing close to surface temperature is going to be liquid down there. That's not a guess, it's a fact.
Assuming it was hot, yes, but can we prove it?
No assumptions involved. Yes, we can prove it. It can be derived easily from basic thermodynamics, and is especially true for wter, which has been investigated quite extensively. There's large books (e.g. Keenan & Keyes) on the properties of water under various situations, and DrJones posted a link earlier in this thread to a phase diagram (a standard way of showing what phases exist for a particular substance as a functionoaf presure and temperature) for water. I don;t have a link ot a phase diagram fro gold.

This message is a reply to:
 Message 251 by simple, posted 02-06-2005 3:35 AM simple has not replied

JonF
Member (Idle past 246 days)
Posts: 6174
Joined: 06-23-2003


Message 259 of 310 (183470)
02-06-2005 9:08 AM
Reply to: Message 254 by simple
02-06-2005 4:20 AM


Re: cool suspects.
I don't know how much that center would have heated up by heat transfer from the hot layer in 6K-10K years
Well, I'm right up here on the surface, and I'm Ok! Just think if I was several thousand kilometers away from the little slice of surficial heat!
Andf you are not thinking. The heat that is transferring up from the lower regions (no matter how or when the Earth was created) is maintaining the surface temperature as it is while significant heat is being radiated to space. The heat that would be transferring to a supposedly cool core has nowhere to go; it would heat the core up until the material just under the surface of the Earth and the core of the Earth would be the same temperature. Heat always flows from hot to cold. The only question is how long it would take.
ruby 3.9 - 4.1---turquise--2.6-2.8, Agate 2.60,Emerald or Garnet -3.5-4.3 , Lapis Lazuli: 2.7-2.9 , amethyst (2.65), jacinth,(4.65 zircon ), topaz (one form of olivine called peridot. 3.22-3.45 )
chrysolite,(3.25), carnelian,(2.65), sardonyx,(2.65),emerald,(4.3)chalcedony,(4.3) , corundum 3.96-4.05. (some old names used in this source). Make several layers, in the mantle area say a hundred miles deep each, and it could match the waves?
Perhaps they could. When you come up with some positive evidence that those layers do exist, we'll be glad to discuss the idea.
There's no material that could stick through the liquid to "prop up" the Earth above the liquid and be slim enough to be invisible to the seismic waves. The liquid down there is pressurized and hot, whatever it is.
What about the liquid itself? If we had 1500 miles of water as the outer core, under the pressure down there, where is is going to go? It couldn't get out. Not if it was under a boundry of something super strong? What about irridium? Or graphite, or, yes, even diamond? (gold, iron, tungston, platinum, etc)
Exactly. The liquid holds up the Earth because it has nowhere to go. Therefore the liquid is pressurized, and we can calculate exactly what pressure it is at. No material is both cool and a liquid at those pressures, so the liquid is hot.
Do we know the precise times for all parts of the core, or outer core?
Yes, although it's not posted on tehe Web as far as I can see, and you are goin to have to dig into the primary literature to find it. You might even have to derive some of it from the raw measurements.
Could it take a bit longer passing through a tougher transition zone, yet still average out to the overall core travel time of 4 seconds?
No, we would see that transition zone in the core.

This message is a reply to:
 Message 254 by simple, posted 02-06-2005 4:20 AM simple has not replied

JonF
Member (Idle past 246 days)
Posts: 6174
Joined: 06-23-2003


Message 260 of 310 (183474)
02-06-2005 9:32 AM
Reply to: Message 255 by simple
02-06-2005 4:30 AM


Re: cool suspects.
If water is the liquid?-and it can only be a liquid within a certain temperature range, then we would have to go with that range, unless we had another liquid that would work. But without water,
Water can only be liquid with certain ranges of temperature and pressure. The more pressure, the hotter the water has to be in order to be liquid. At some pressures liquid water is impossible at any temperature (and at some temperatures liquid water is impossible at any pressure).
Water under the pressure of the outer core is not liquid, not at any temperature. Look at the phase diagram for water taht DrJones linked to way back in this thread: The Phase Diagram of Water. The highest pressure at which liquid water can exist is about 1,000,000,000 Pascals (145,000 pounds per square inch, or about 10,000 atmospheres) and at that pressure the temperature of the water has to be at least 620K (656°F). But the pressure at the top of the outer core is 140,000,000,000 Pascals (see Earth which is 100 times too high for liquid water to exist at any temperature.

This message is a reply to:
 Message 255 by simple, posted 02-06-2005 4:30 AM simple has not replied

JonF
Member (Idle past 246 days)
Posts: 6174
Joined: 06-23-2003


Message 261 of 310 (183479)
02-06-2005 9:46 AM
Reply to: Message 256 by simple
02-06-2005 4:48 AM


Re: cool suspects.
Seems to me, if someone had a good case, like that the core was hot, that they should be able to present it
It has been presented. Many times.
The outer core is liquid.
The outer core is pressurized because it is supporting all the Earth above it.
No material anywhere near as cool as Earth's surface temperature is liquid at the pressure of the outer core.
Therefore, the temperature of the outer core is not anywehre near as cool as Earth's surface temperature.
Give up protesting that nobody has "nailed it" and start addressing the evidence. The density of the outer core is between 10 g/cm3 (624 pounds per cubic foot) and 12.4 g/cm3 (768 pound per cubic foot) (this is, the density varies at different levels within the outer core). The pressure at the top of the outer core is 140,000,000,000 Pascals (20,000,000 pounds per square inch or about 1,400,000 atmospheres). There is no material (and we know a lot about a lot of materials, including gold and water and diamond) that is that dense and anywhere near Earth's surface temperature and liquid at that pressure. You want to argue otherwise, present your material and your evidence.

This message is a reply to:
 Message 256 by simple, posted 02-06-2005 4:48 AM simple has not replied

Coragyps
Member (Idle past 812 days)
Posts: 5553
From: Snyder, Texas, USA
Joined: 11-12-2002


Message 262 of 310 (183497)
02-06-2005 12:04 PM
Reply to: Message 255 by simple
02-06-2005 4:30 AM


Re: cool suspects.
If water is the liquid?-and it can only be a liquid within a certain temperature range, then we would have to go with that range, unless we had another liquid that would work. But without water, it takes a lot of the fun away for me.
Well, your fun is over, then, because as you've been told several times now water isn't dense enough to sink to that spot, and there's no material strong enough to build your silly-assed 3000-mile diameter shell over the core to hold a mantle with a specicic gravity of 5 up out of a light fluid like that.
Mods, can we get this goofyness shut down? Simple is repeating the same old stuff from 200 posts ago.

This message is a reply to:
 Message 255 by simple, posted 02-06-2005 4:30 AM simple has not replied

Percy
Member
Posts: 22606
From: New Hampshire
Joined: 12-23-2000
Member Rating: 4.9


Message 263 of 310 (183550)
02-06-2005 3:45 PM
Reply to: Message 250 by simple
02-06-2005 3:15 AM


Re: cool suspects.
Hi Simple,
You're asking lots of good questions, which is exactly what you want to be doing. The answers seem to be spread across multiple posts instead of being contained in a single post, but I think all the information is there. Let me take a stab at getting many of the questions related to my post answered in one place.
  1. How do we know that the outer core is liquid?
    Through seismographic analysis. Seismographs around the world measure the arrival times of vibrations from every earthquake. Earthquake vibrations are transmitted through two types of waves, P and S (P for Primary or compression waves, and S for Secondary or Shear waves - there are also L or longitudinal waves that only move on the earth's surface). The details of these two types of waves aren't essential, though we can delve into it if you're interested, but the key point is that the waves are reflected and refracted as they travel through the earths interior, and S waves cannot travel through liquids. So when an earthquake occurs in Peru then seismographs around the world can record the time and intensity of the arriving waves, and subsequent analsis tells us the internal structure of the earth. In particular it tells is that there is an outer core of liquid.
    If you click on this page 95 from Earth Story to see it full size you'll get a rough idea of the process, which is briefly described in the text at the lower right:

    Click for larger image
  2. How do we know the liquid portion is hot?
    First you have to accept as true some relatively simple physical principles. If you reject these principles then you'll not accept that the liquid portion is hot, but in that case you'll be rejecting much of science and we'd no longer be having a rational conversation.
    If you keep a gas at a constant temperature, then compressing the gas will eventually turn it liquid. Compressing it further will turn it into a solid. In other words, increasing pressure causes materials to turn from the gaseous state to the liquid state and finally the solid state.
    If you increase the temperature of a solid you'll eventually turn it to a liquid and then a gas.
    Elements in a gravitational field sort themselves by density, with the most dense at the bottom of the gravitational field.
    The deeper you go within the earth the greater the pressure, just as the deeper the dive in the ocean the greater the pressure.
    If you accept the above, then you can arrive at the conclusion that the liquid must be hot through simple logical thinking: If we take a metal like iron and heat it to the melting point here on the earth's surface, that would correspond to a temperature 2800oF. Now if we increase the pressure while keeping the temperature constant we can turn it back into a solid. Actual for-real laboratory experiments indicate that a nickel/iron core turns from a solid to a liquid at the pressures of the inner core at a temperature of 9000oF.
  3. How do we know that the inner and outer core are composed of nickel/iron?
    This is from page 100 of Earth Story:
    The commonest type of meteorite, called a chondrite, is predominatnly composed of four elements - iron, oxygen, magnesium and silicon. Another common meteorite consists of an iron-nickel alloy. If the Earth has the same composition as a chondrite, but with most of the iron in the same metallic form as in the iron-nickel meteorites, then this would produce a planet with a similar density to the Earth's.
    So your guess about gold at the core is a good one because gold is a very dense element. But the problem is that gold is a very rare element. While the inner and outer core must also consist of gold and uranium and lead and other dense elements, the relative abundance of these elements in the solar system compared to iron and nickel is so much less that their contribution isn't usually considered in laymen level presentations. I could find nowhere on the net where components other the nickel and iron in the core were mentioned.
  4. How do we know the interior of the earth is denser than the outer layers?
    This is a simple to verify. If you check the article on the earth's core at Wikipedia you'll see that the average density of the earth (a derived value arrived at by dividing the earth's mass (an easily measured quantity) by it's volume (an easily calculated quantity since we know the radius)) is 5505 kg/m3, while the average density of material at the surface is only 3000 kg/m3, so the density of the material at greater depths must be much larger.
  5. How do we know the core is denser than the rest of the earth?
    I was able to find little about direct measurements, but apparently there's something called a gravity measurement that indicates that the core is far denser than the mantle. Therefore, the mantle is denser than the rocks at the earth's surface, and the core is denser than the mantle. This makes sense since pressure, and therefore density, increases with depth.
  6. How do we know that water is not the liquid that makes up the outer core?
    If you accept the above temperature and density estimates for the outer core, and if you understand the phase information presented by others for water, then you'll understand that it couldn't possibly be water, not at 9000oF and a density above 6000 kg/m3.
    Also, water is not dense enough to form a layer below rock. The densest materials sink beneath the less dense materials, and water is nowhere near as dense as rock.
    Though the earth's magnetic field is not evidence against water, an aqueous outer core is incompatible with current theory since it couldn't contribute to this field.
Help this helps! Others here are also giving you very good information, so I hope you listen to them, too. I agree with what someone posted about this thread beginning to appear repetitive.
--Percy
This message has been edited by Percy, 02-06-2005 15:47 AM

This message is a reply to:
 Message 250 by simple, posted 02-06-2005 3:15 AM simple has replied

Replies to this message:
 Message 264 by Coragyps, posted 02-06-2005 4:06 PM Percy has not replied
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 Message 270 by simple, posted 02-06-2005 10:00 PM Percy has replied

Coragyps
Member (Idle past 812 days)
Posts: 5553
From: Snyder, Texas, USA
Joined: 11-12-2002


Message 264 of 310 (183553)
02-06-2005 4:06 PM
Reply to: Message 263 by Percy
02-06-2005 3:45 PM


Re: cool suspects.
Good, clear post, Percy. I should work on patience...
How do we know the core is denser than the rest of the earth?
Let me add here: the most important way that we know this is because heavy stuff sinks! Any material with a greater density that that of its surroundings will try to settle to its own level. If you look for even a moment at the strength of material required for a "barrier" or "diamond shell" or what-have -you, you'll see that it just can't work! 1500 miles of rock, specific gravity 4.5, above a body of water under enough pressure to get it to specific gravity 1.5 will do as an example. That's (4.5 - 1.5) x 62.4 x 1500 x 5280 pounds held up by each square foot of this "barrier" - and if it's a couple of thousand miles across itself, it has several square feet of area!
Look at what you're proposing, Simple. Think about it.

This message is a reply to:
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JonF
Member (Idle past 246 days)
Posts: 6174
Joined: 06-23-2003


Message 265 of 310 (183560)
02-06-2005 4:31 PM
Reply to: Message 263 by Percy
02-06-2005 3:45 PM


Is it Simple or Cosmo
Percy, are you aware that it's not certain which you are addressing, Simple or Cosmo? See the last sentence of Message 254.

This message is a reply to:
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CK
Member (Idle past 4205 days)
Posts: 3221
Joined: 07-04-2004


Message 266 of 310 (183562)
02-06-2005 4:35 PM
Reply to: Message 265 by JonF
02-06-2005 4:31 PM


Re: Is it Simple or Cosmo
I wondered about this before - "simple" is refering to moving on from ideas that i'm sure that Cosmo proposed.

This message is a reply to:
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Admin
Director
Posts: 13081
From: EvC Forum
Joined: 06-14-2002
Member Rating: 2.4


Message 267 of 310 (183573)
02-06-2005 5:06 PM
Reply to: Message 254 by simple
02-06-2005 4:20 AM


Re: cool suspects.
simple writes:
[PS moderators, could you please mail cosmo his password, he (I)is using simple's at the moment, on loan, thanks]
There's a "Lost your password" link on the login page.

--Percy
EvC Forum Director

This message is a reply to:
 Message 254 by simple, posted 02-06-2005 4:20 AM simple has replied

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DrJones*
Member
Posts: 2293
From: Edmonton, Alberta, Canada
Joined: 08-19-2004
Member Rating: 5.9


Message 268 of 310 (183589)
02-06-2005 8:20 PM
Reply to: Message 255 by simple
02-06-2005 4:30 AM


Re: cool suspects.
Didn't I do that?
No you haven't shown a single calculation for the pressure and temperature at the core for your model. You've provided absolutely no evidence for anything.
If water is the liquid?-and it can only be a liquid within a certain temperature range, then we would have to go with that range, unless we had another liquid that would work
As others have already pointed out water exists as a liquid within a certain temperature and pressure range. As the pressure increases the water's temperature has to increase for it to remain a liquid. The pressure at the core is too high for water to exist as a liquid no matter what it's temperature. If you want to refute this please show your calculations for the pressure and temperature at the core. I doubt you will though because it's obvious that you don't have the most basic grasp of science.

*not an actual doctor

This message is a reply to:
 Message 255 by simple, posted 02-06-2005 4:30 AM simple has replied

Replies to this message:
 Message 271 by simple, posted 02-07-2005 1:38 AM DrJones* has replied

simple 
Inactive Member


Message 269 of 310 (183602)
02-06-2005 9:35 PM
Reply to: Message 267 by Admin
02-06-2005 5:06 PM


Re: cool suspects.
thanks

This message is a reply to:
 Message 267 by Admin, posted 02-06-2005 5:06 PM Admin has not replied

simple 
Inactive Member


Message 270 of 310 (183607)
02-06-2005 10:00 PM
Reply to: Message 263 by Percy
02-06-2005 3:45 PM


Re: cool suspects.
quote:
and subsequent analsis tells us the internal structure of the earth. In particular it tells is that there is an outer core of liquid.
Yes, of course, agreed.
quote:
Elements in a gravitational field sort themselves by density, with the most dense at the bottom of the gravitational field.
Now this one is a good general rule. But I could see some exception if the earth was a creation, as long as the overall density balance was right. In other words, the liquid, unless ned is right, (which I'll respond to after this post)-could fit into the evidence even if cooler. All we really know is that it is a liquid, not that it is a certain density??
quote:
So your guess about gold at the core is a good one because gold is a very dense element. But the problem is that gold is a very rare element.
Not a problem for creationists, of course. Only for the big bang type scenarios!
quote:
I could find nowhere on the net where components other the nickel and iron in the core were mentioned
Yes, not your garden variety concept, questioning if it must be hot!
quote:
How do we know the interior of the earth is denser than the outer layers?
Right. Got that one quite a while ago, that must have been early in the discussion, where I quetioned everything, until shown we had good pfoof. Agreed, it is dense, to average out to the standard 5.5 or so overall, denser in center, less so near surface.
quote:
If you accept the above temperature and density estimates for the outer core, and if you understand the phase information presented by others for water
I'm just going to get to that one in the next post. If I remember, though, early on in this thread the one who brought up the phase diagram of water to begin with accepted it could exist down there.
quote:
Also, water is not dense enough to form a layer below rock
Two points here, one is Walt Brown's idea thet rock would be watertight even I think he said, 5-10 kilometers (or miles) down. He only had his escaping after some catastrophic event. Second, I did post yesterday, about how some gems and stones (like olivine) could reduce heat transfer, and possibly, form a better water barrier than mere rock?

This message is a reply to:
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Replies to this message:
 Message 272 by JonF, posted 02-07-2005 7:58 AM simple has not replied
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