Is there heat generation at the center of the earth?

[cosmos0]

Hello everybody,

 

I am proposing a heat-diffusion model in spherical coordinates applied to the earth. The main idea is that the earth was a hot ball of homogeneous temperature when the earth formed, that did cool down over time due to heat-diffusion. As we know earth formed from an accretion disk, therefore, the homogeneous temperature at earth formation assumption appears to be reasonable. The model provides the temperature-depth profile of the earth at different ages. The model makes two predictions:

(1) 4.4 billion years after earth formation, the temperature gradient in the first kilometer of the earth's crust is about 3 degree Celsius per 100 meters. This is well in agreement with current estimates.

(2) 4.4 billion years after earth formation, the earth crust thickness is around 70-80 km. This is in agreement with the maxima of the continental crust; however, most of the continental crust is 40-45 km thick, and oceanic crust 7-10 km thick.

 

The challenge is to explain the gap from prediction (2).

Please find enclosed the link to the manuscript: http://fr.calameo.com/books/000145333b9055bc4b717

 

Your comments and ideas are welcome..

Edited March 8, 2013 by ydoaPs
Removed file by request of OP

[swansont]

The core is under pressure from gravitational compression; if you decrease the gravitational potential energy when you form the planet that energy has to go somewhere. Also, there is radioactive decay, so there is continued release of energy that decreases with time.

[alpha2cen]

The earth orbit has been constant from the beginning? Air temperature was higher than the used value, or the rest heat was generated from the other sources.

Edited January 13, 2013 by alpha2cen

[Semjase]

There's another potential theory of the Earth's heat source is gravitational heating,

this is when the surface energy of earth is amplified through the work done by gravity to the

moving molecules of interior of the Earth as you move to it's center. A German researcher

used this theory to describe change of temperature due to altitude change. He also tested

a colunm of air in a sealed container isolated in a vacuum and found a temperature difference in the air

was continually maintained between the top and bottom of the sealed container.

[alpha2cen]

heating source = radioactive decay energy + a small quantity of the tidal heating energy (the distance form the sun or the moon is shorter than the present)+ others ?

[Enthalpy]

...Earth was hot... when it formed, that did cool down over time due to heat-diffusion...

...continental crust is 40-45 km thick, and oceanic crust 7-10 km thick.

 

You miss other sources of heat, especially radioactivity, estimated to contribute half as much as the initial heat last time I saw a figure.

 

Heat is transferred by convection. Diffusion should have been too inefficient.

 

Lighter materials make thicker hence higher continents, denser materials make thinner hence lower oceanic floor, because they're near hydrostatic equilibrium.

 

Did you notice that oxygen is in limited amount as compared to metals and oxides are lighter, so a limited thickness of oxides floats over metals?

 

Then you miss all the dynamic process on Earth, especially the creation of new oceanic floor and its following subduction.

 

More generally: why make a model that ignores a century of well-established knowledge? To my eyes, it's a big effort to produce inevitably wrong results.

[alpha2cen]

Hello everybody,

 

I am proposing a heat-diffusion model in spherical coordinates applied to the earth.

Your comments and ideas are welcome..

The thermal diffusivity is calculated at the average temperature region? Is it too high? Thermal diffusivity is a temperature dependent parameter.

Edited January 14, 2013 by alpha2cen

[sunnydart]

I have two theory-

1.WE all Know the fact on increasing compression that is direct pressure to any matter cause increase in temperature.

2. Suppose if metallic ball is rubbing on its surface with high pressure & Friction generates lots of heat..

[alpha2cen]

 

1.WE all Know the fact on increasing compression that is direct pressure to any matter cause increase in temperature.

 

How to generate the heat? Do you have any theory?

[sunnydart]

Theory- At Constant Volume- Temperature increase on increasing the pressure.

[John Cuthber]

Counter theory

At constant volume nothing moves up or down. No work is done (because the forces don't move through any distances).

Since no work is done there is no energy release.

Because there is no energy transfer, the temperature remains constant.

 

On the other hand, if radioactive decay causes heat to be released within the earth then it can produce convection currents.

 

It's the heat that generates the movement, not the other way round.

[sunnydart]

Mr. John Cuthber- At cONStant vOLume OF sOLID BOTH air & Liquid can move inside at any place because of difference in their Potential energy BUt..........................

[John Cuthber]

But no net work is done.

It was once, when the earth was young.

What are you saying provides that potential energy?

[sunnydart]

Rotation of earth provide potential energy ..simple...

[swansont]

Rotation of the earth is kinetic energy, and you need to conserve angular momentum. Some undoubtedly gets converted to heat, but probably not at the core, and probably not a large amount. I imagine there is some heating from tides, for example.

[sunnydart]

Angular Momentum J=I*W. Where w is rotation of earth which is constant . & I - Inertia That depend on density of earth which is constant. so value of J is almost constant & responsible for maintaining heat temperature inside & out side of earth.

Edited January 23, 2013 by sunnydart

[John Cuthber]

Rotation of earth provide potential energy ..simple...

No it doesn't: simple.

[swansont]

Angular Momentum J=I*W. Where w is rotation of earth which is constant . & I - Inertia That depend on density of earth which is constant. so value of J is almost constant & responsible for maintaining heat temperature inside & out side of earth.

 

 

What is the supposed connection between angular momentum and temperature? The temperature (especially outside) is not a constant, and a fact I am especially aware of this morning.

[John Cuthber]

Angular Momentum J=I*W. Where w is rotation of earth which is constant . & I - Inertia That depend on density of earth which is constant. so value of J is almost constant & responsible for maintaining heat temperature inside & out side of earth.

So far as it goes anywhere, that proves that you are wrong.

It suggests that the momentum is constant and, therefore, the energy is constant (since I doesn't change, and J is constant, it can't change w, so it can't change

1/2 I w squared).

But we know that the earth is radiating energy into space (because it's warm) so it must be losing energy.

If it's losing energy then it can't be getting that energy from it's rotation which is constant.

(There are small effects due to tides and hypothetical effects due to gravity waves to consider, but those are small and immeasurable small respectively)

[cresol]

becaus the earth ha

s its own potential energy due to rotation, then its temperature will therefore be increased at increased pressure.....simple

 

becaus the earth ha

s its own potential energy due to rotation, then its temperature will therefore be increased at increased pressure.....simple

[Ophiolite]

becaus the earth ha

s its own potential energy due to rotation, then its temperature will therefore be increased at increased pressure.....simple

 

becaus the earth ha

s its own potential energy due to rotation, then its temperature will therefore be increased at increased pressure.....simple

Could you show me the maths for that?

 

Could you show me the maths for that?