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Plate tectonic mechanism ?

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Sorry about taking so long to respond, its been a rough couple of months around our house. I had hoped to get some time to do research, finally got a break over the Holiday, and things are getting back to normal now.

 

Would you like to explain this.

It makes no sense to me

 

Quote: As the mantle moves downward the oceanic crusts are loaded with proportional amounts of GPE. The only compression relieving mechanism available in this situation is the continents will need to overcome the resistance that they have to moving to a lower energy state by sliding towards the nearest convergent boundary available. In the Atlantic’s situation this would undoubtedly be greater then what the Pacific’s oceanic plates are subjected to. For example: the energy required to move N. America over the subducted Farallon and then Pacific oceanic plates would be much greater than with what the Pacific expends just subducting into an adjacent convergent trench

 

The GPE increases in proportion to the building compression in the oceanic plate, compression created by the two opposing continents as they move towards each other, as the mantle incrementally subsides. The opposing continents (N. America/Eurasia and S. America/ Africa) will hold their connected oceanic crust in a raised and increased state of higher GPE. The resulting compression in the oceanic plates will eventually begin to push their opposing and connected continental plates away in the opposite directions.

 

The Pacific oceanic plate on the other hand will need to move very little in relation to the mantle that is subsiding beneath it, as the Pacific oceanic plate slides into its adjacent convergent trenches and unloads its GPE derived compression. The GPE in the Atlantic has no nearby trenches and thus will need to, over a much longer period of time, move the adjacent and connected continental masses to lower its compressive load of GPE.

 

As has been shown in my previous post, North America’s periodic movement over the Yellowstone hotspot shows the kinetic response to the GPE driven compression in the Atlantic oceanic plates. This movement of a much heavier continent over the subducted remnants of two oceanic plates and their divergent boundary involves additional levels of resistance that extends the time it takes to move N. America over it.

 

 

 

Nor does showing pictorial sequences of allegedly convergent or divergent boundaries all the same distance apart.

 

Allegedly? They’re not what I think they are? ^_^

They were described as simple models, just similar to the convergent and divergent boundaries being discussed. Their overall size was not important, only the arrangement of various components; the oceanic plates, the divergent and convergent boundaries and the continents in regards to their specific position within the dynamic system presented. I reused a template to save time. The continents were not accurately portrayed either in size or shape, to no apparent detrimental effect as I can see. The images only had to express the alleged movements I was describing.

 

 

 

I would suggest you need to conduct some old fashioned geological investigation before offering some of the above statements of geological history.

 

You should check that the actual rocks found in the field conform to your theory.

 

Are they of the correct Age?

Are they of the correct type - sedimentary or igneous?

What is the orientation of their bedding?

Are they the right way up or is there an inversion unconformity?

 

I did say;

 

"the 140 million year age estimate at the Romanche Fracture Zone is quite possible with this model."

 

The possibility of, and evidence for, the Earth having extended periods of no seafloor generation, such as when at least one section of the Atlantic ridge was near the oceanic surface when mountain ranges around the world were rising, would be expected with this model.

 

I have again located research that further supports this model’s claims. The following paper describes a 554 million year record of the periodic outward and inward displacement of the earth’s crust. The paper shows that the 56 known cycle periods varied between 5 and 15 million years with the average being 10 Ma.

 

http://www.geoconvention.com/archives/2013/183_GC2013_Episodic_Tectonics.pdf

 

Episodic Tectonics in the Phanerozoic Succession of the North American Arctic and the “10 Million Year Flood”

Ashton Embry, Geological Survey of Canada, Calgary, aembry@nrcan.gc.ca

Benoit Beauchamp, University of Calgary, Calgary, bbeaucha@ucalgary.ca

Keith Dewing, Geological Survey of Canada, Calgary, kdewing@nrcan.gc.ca

James Dixon, Geological Survey of Canada, Calgary, jdixon@nrcan.gc.ca

 

Conclusions

“Fifty-six, large magnitude sequence boundaries have been delineated in the Phanerozoic succession of Arctic North America. The characteristics of the boundaries indicate that they were primarily generated by tectonics. The boundaries occur with an approximate 10 million year frequency (9.8 +/- 3.1). Each boundary was generated during a tectonic episode interpreted to reflect a mantle-driven, plate tectonic reorganization and consequent changes in regional stress fields. Such episodes likely lasted for a few million years and were separated by longer intervals of relative tectonic quiescence. There are indications that the recognized tectonic episodes affected basins throughout the world.”

 

“A given tectonic episode began with the initial uplift of the basin margin (start of base level fall) and ended with the collapse and marine flooding of the margin (maximum flooding surface). The sequence boundary was generated during the tectonic episode and represents the time of maximum uplift and basinward extent of the unconformity.”

This model’s previously stated prediction that there is a clear separation between the thermal expansion portion of the overall cycle period, as in when the mid ocean ridge infill occurs, and the distinct times when increased amounts of GPE develop, as in when the mantle subsides, is clearly recognized by the above paper’s authors.

 

“It is estimated that the duration of each of the tectonic episodes was in the range of a few million years and was significantly shorter than the intervening times of tectonic quiescence.”

 

They further acknowledge that the paper’s subject is global in its scope.

 

“In terms of the possible global extent of the recognized events, it is worth noting that all of the 18 major, tectonic, sequence boundaries recognized by Sloss (1988) for the Phanerozoic of the North American continent are present in our compilation for the Arctic.”

 

 

“A more detailed literature search for the Triassic (Embry, 1997) has revealed that all the Triassic, tectonically-generated sequence boundaries recognized in the NA Arctic are present in numerous basins in North America, Europe and Asia and were also tectonically generated in those areas.”

 

Due to the thermal origin of the phenomena, the paper further supports this model’s contention that the cycles would correspond to the observed carbon excursions in the geologic record. That the outward displacement of the mantle, that produces both divergent mid-ocean ridge movement and strain energy derived magma in the crust/mantle boundary, would include the release into the ocean a significant thermal component that would then show in the record of known carbon excursions.

 

“ It has also been determined that 16 of the18 Cambrian-Pliocene mass extinctions identified by Bambach (2006) coincide with an identified tectonic episode and that many of the tectonic episodes correlate with significant carbon isotope excursions (Saltzman and Thomas, 2012).”

 

I feel it is important to my argument to continue to point out this model’s ability to make accurate predictions of observations. In post 31 I wrote about this link between these tectonic cycles and their link to climate;

 

The mantle in this model is displaced by the thermal expansion of the outer core's liquid iron from the increased amplitude of current within the magnetic field's magnetohydrodynamic generator. The mantle's outward movement, against the force of gravity, produces a strain energy response as the mantle's viscosity resists the expansion, creating thermal heating of the mantle material as the strain tension is released.

 

 

The strain energy response and thermal release increases proportionally to the distance from the mantle-core boundary, culminating at the crust-mantle boundary with maximum expansionary movement and strain energy thermal heating. The mantle's outer boundary surface area is stretched out and torn producing localized pressure reduction thus allowing melting of the surrounding surface area materials.

This thermal heating of the crust-mantle boundary coincides with the expansionary movement of the crust by the displaced mantle, giving researchers a way to measure and calibrate the thermal forcing of Earth's ocean and atmosphere to historic periods of plate tectonic expansion and contraction.

 

 

As an example, the extension of the Basin and Range Area is dated to the Miocene Epoch (5.3 - 23.03 MYA). The province is believed to be the result of tectonic extensional processes that began around 17 MYA (million years ago) in the Early Miocene. It was considered a warmer climate period than the following Pliocene and Pleistocene Epochs that were cooler periods of climate that coincide with the Himalayan and Andes mountain building periods. These structures would require large scale subduction and displacement of crustal gravitational potential energy into the folded and raised rock strata. These mountain structures occurred while the Earth's climate went into a period of Ice Ages.

 

 

This model gives significant, but not unambiguous, evidence that the thermal variability of the outer core produces coordinated geologic restructuring and climate forcing.

I would also include the following paper to further strengthen this model ability to describe the observable world.

http://figshare.com/articles/Repeated_slab_advance_8211_retreat_of_the_Palaeo_Pacific_plate_underneath_SE_China/1328415

Repeated slab advance–retreat of the Palaeo-Pacific plate underneath SE China
Yao-Hui, Jiang; Guo-Chang, Wang; Liu, Zheng; Chun-Yu, Ni; Long, Qing; Zhang, Qiao
(2015): Repeated slab advance–retreat of the Palaeo-Pacific plate underneath SE China. figshare.
http://dx.doi.org/10.6084/m9.figshare.1328415Retrieved 04:37, Sep 08, 2015 (GMT)

"Integrating these observations, we propose a repeated slab-advance–retreat model for the late Mesozoic magmatic evolution of southeast China. Palaeo-Pacific plate subduction underneath southeast China initiated in the Late Triassic Rhaetian and reached southern Jiangxi by ca. 197 Ma, followed by slab rollback during 197–191 Ma and by slab break-off at ca. 189 Ma. Then slab advance was reestablished with the northwestward subduction approaching southern Hunan at ca. 178 Ma. From ca. 174 Ma, slab rollback reinitiated and gradually migrated from inland to the coastal area. This repeated slab-advance–retreat model is helpful to further understand the geodynamic mechanism of the late Mesozoic tectono-magmatism and related metallogenesis of southeast China."

 

The episodic geologic timing, seen in the papers above, matches very closely the timing intervals seen in the other examples in this thread, for example, the Yellowstone hotspot’s progression across western N. America that is seen in the image below.

 

post-88603-0-35754400-1452386938_thumb.jpg

 

 

Incidentally no one here is trying to cleverly trap you.

 

I never mentioned the word "clever". ^_^

 

Arc,

 

In the argument about fast mountain building and episodic growth spurts:

1) You show some problems with the standard model. Great, very interesting!

2) You add some kind of alternative explanation (in the form of cartoons). OK good you're thinking at least! Now just add the maths!

3) You add some evidence -- midocean ridges bulge upwards.

 

Here are the problems:

• The evidence does not support your theory because your model is nothing more than cartoons -- you really need those numbers!

 

Billiards, here are your problems:

That wonderful paper I just showed above is primarily the result of field work. Physically examining the various sites and taking samples, drilling cores and dating the contents. This model is built from these and many other such field studies. Most of these are of the last 10 years.

 

Plate movement through mantle convection and sea floor flattening as proposed by Parsons and Sclater is obsolete, do you see any explanations within their maths that allows you to explain the mantle oscillations that are revealed in my previous post and the additional supporting evidence I have shown in this post.

 

As this thread has repeatedly shown; mantle convection and Parsons and Sclater does not fit the reality of the observable world;

 

1. Mountain ranges on multiple continents and the extraordinary elevation of the Mid-Atlantic ridge as this model proposes were built during globally synchronized periods of geologic history. And as I have shown, occurred simultaneously with the uplift of the Mid-Atlantic Ridge to the surface.

 

2. Then add to this the evidence of:

 

“Fifty-six, large magnitude sequence boundaries have been delineated in the Phanerozoic succession of Arctic North America. The characteristics of the boundaries indicate that they were primarily generated by tectonics. The boundaries occur with an approximate 10 million year frequency (9.8 +/- 3.1). Each boundary was generated during a tectonic episode interpreted to reflect a mantle-driven, plate tectonic reorganization and consequent changes in regional stress fields. Such episodes likely lasted for a few million years and were separated by longer intervals of relative tectonic quiescence. There are indications that the recognized tectonic episodes affected basins throughout the world.”

 

The standard model is unable to address these newest and accurate observations. And all the maths of the standard model's mantle convection do not help to understand them. The SM maths of convection describe an imaginary world, one assumed to be this one if you can ignore these mantle oscillations.

 

• One obvious consequence of your model is that there would need to be compressive faults at the mid ocean ridges to accomodate the crustal shortening. There aren't any observed in nature. BOOM your theory is wrong. (truth hurts sometimes)

 

billards, you have been looking at them the whole time, but just like all of the other details, they have been overlooked due to the poor fit that the standard model has to the real natural world.

 

This image below is a typical cross section of the Pacific. It is not even 26 km’s wide and just 500 meters high.

 

post-88603-0-50047300-1452387216_thumb.png

 

Here is a 550 km wide 2400 m high cross section of the Atlantic ridge axis; this is just a portion of the overall structure that extends over 1600 km wide and averages 3.2 km high.

 

post-88603-0-29252700-1452387305_thumb.png

 

When you apply the observations of the various papers I have presented in support of this model the Atlantic MOR reveals that it was compressed to the point that the ridge was crushed and fractured in uncountable faults parallel to the ridge that then moved vertically to relieve the compressive strain, because as was shown, it was raised to the ocean’s surface for several million years.

 

That is another prediction of observation that this model has routinely furnished, something you physically can see with your own eyes, which greatly distinguishes it from the standard model.

 

 

• There is already a perfectly good *quantitative* description of the mid ocean ridge bulge (Parsons and Sclater).

 

This is where the standard model is between a rock and a hard place.

 

The Parsons and Sclater is from clear back in 1977. They had no idea that in 26 years Nature 423, 499-505 (29 May 2003) would publish a paper that shows a completely different, and more important, accurate set of observations of what is actually occurring at the same crust/mantle boundary area of the Mid Atlantic Ridge that the Parsons and Sclater was only guessing at.

 

The mantle was shown at that period of geologic time to be actually oscillating every 3-4 million years.

 

Add to this the evidence of the "Fifty-six, large magnitude sequence boundaries have been delineated in the Phanerozoic succession of Arctic North America." and the "Repeated slab advance–retreat of the Palaeo-Pacific plate underneath SE China"

 

The standard model is hopelessly outdated and incapable to address these realities.

 

 

This latter point relates to your second argument about the height of transform ridges. Here you:

1) You show that transform ridges bulge upwards and this is not explained by the Parsons and Sclater model. Great, how interesting!

2) You ramble on for a while without making a coherent point.

 

Presumably here you mean to destroy the standard model again and thereby free your path to our hearts and minds. However, just because the Parson and Sclater model does not explain EVERYTHING does not mean that it explains NOTHING. To me, the failure of the Parsons and Sclater model at the these locations reveals that the underlying physics used in that model does not apply in these situations. Parson and Sclater model is a thermal model of topography, and therefore the bulges at tranform faults are not thermal features. Besides, non of this helps you to escape the fact that there are still no compressive faults at the mid-ocean ridges. And that for me is the killer blow to your theory. You could disprove Parsons and Sclater all day long and it wouldn't make the darndest difference.

 

"Presumably here you mean to destroy the standard model again and thereby free your path to our hearts and minds. However, just because the Parson and Sclater model does not explain EVERYTHING does not mean that it explains NOTHING"

 

The question is;

 

Is Parson and Sclater model even relevant considering the evidence that the mantle has been periodically oscillating for 545 million years? What mechanism does the standard model propose to explain this? Would it claim it originates, and is contained in the crust/mantle boundary, so as to leave it an opening to keep mantle convection viable? Is mantle convection even possible with the mantle displacing outward and inward for 545 million years from outer core thermal expansion and contraction?

 

I would say it is safe to assume the standard model and Parson and Sclater is irrelevant considering the mantle has oscillated for at least 545 MY, and has likely always oscillated.

 

And that for me is the killer blow to your theory.

 

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!

Moderator Note

 

I have split off Kalopin's post and two follow ups to it.

 

This is Arc's thread within which he gets to test his theory and defend it against all-comers. It would get confusing if we allowed more than one speculation in a single thread - and we have plenty of digital real estate so I have created a new thread for Kalopin's idea.

 

If you would like me to rename the new thread then PM me

 

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The current standard model is an accumulation of theories of many different geologists, all of which being dependent to a certain degree on the accuracy of the earlier works. It’s like everything that makes up current theory is limited by its genetic background. I wanted to build from scratch and see what could develop. I would like to say up front that Arthur Holmes was a scientist that I really admire but I said “from scratch” and his mantle convection is the foundation of the current model. It set the course that brought us to these complexities that generate solutions like mantle plumbs and the long list of “fix’s” that keep plumbs viable. Mr. Holmes himself early on referred to his mantle convection as a speculation.

With this freedom I was able to take a fresh look at the evidence. What stood out to me are the obvious signs of contraction by way of subduction trenches and mountain ranges that are balanced by the evidence of expansionary movements in various planations and extreme extensional processes such as the Basin and Range area. I realized the curving and movement of the Island Arcs towards the trenches could also be part of this expansion/extension from surface tension pulling on the arcs. From this beginning I was able to add each example that is now shown in this model. From the breakup of continents to the current sea floor spreading, a model using a multi-million year thermal expansion mechanism is one part of a thermal cycle that provides multi-million year contraction that produces large degrees of subduction and mountain building. It is a very simple model based on the outer core having a thermal cycle encompassing tens of millions of years from forcing by a very small and gradual variable current amplitude.

Nice theory arc. Hats off to you for not placing assumptions on other peoples prior work. It can pay to rationalize things for ones self.

 

This is off topic, so its ok if youre not interested in answering, but I would genuinely be interested to know. How much would the Earth shrink if the core was room temp?

Edited by Questing

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..... How much would the Earth shrink if the core was room temp?

That would be the end result after billions of years if the Earth does not get swallowed by the expanding Sun. All tectonic plate movement would have stopped and I'm assuming you are referring to a time when the entire Earth is at room temperature.

It is virtually impossible to ever imagine this ever happening as there will always (well for many more billions of years) be some radioactivity in the Earth keeping it warm.

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That would be the end result after billions of years if the Earth does not get swallowed by the expanding Sun. All tectonic plate movement would have stopped and I'm assuming you are referring to a time when the entire Earth is at room temperature.

It is virtually impossible to ever imagine this ever happening as there will always (well for many more billions of years) be some radioactivity in the Earth keeping it warm.

Thank you Robitty. Yes I'm aware of the details you have provided. I'm just curious how much diameter or volume is added to the Earth due to heat expansion?

Edited by Questing

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Thank you Robitty. Yes I'm aware of the details you have provided. I'm just curious how much diameter or volume is added to the Earth due to heat expansion?

if we looked up coefficient of expansion for magma maybe we would get some idea. What would the average temperature of the Earth be?

found one site Thermal expansion coefficient of the magma

5·0 × 10^−5/°C http://petrology.oxfordjournals.org/content/48/7/1295/T3.expansion

 

Is that in units of %/degree C? So what is the temperature change?

 

This notes gives us a summary http://www.cliffsnotes.com/study-guides/geology/inside-the-earth/geothermal-gradients

But I couldn't see any quick estimate of the average internal temperature.

 

But let's say it cooled by 3000 degrees does that equate to just 0.15% change in volume (if I have done it right) and the Earth's volume is quite enormous.

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if we looked up coefficient of expansion for magma maybe we would get some idea. What would the average temperature of the Earth be?

found one site Thermal expansion coefficient of the magma

5·0 × 10^−5/°C http://petrology.oxfordjournals.org/content/48/7/1295/T3.expansion

 

Is that in units of %/degree C? So what is the temperature change?

 

This notes gives us a summary http://www.cliffsnotes.com/study-guides/geology/inside-the-earth/geothermal-gradients

But I couldn't see any quick estimate of the average internal temperature.

 

But let's say it cooled by 3000 degrees does that equate to just 0.15% change in volume (if I have done it right) and the Earth's volume is quite enormous.

Thank you for going to some considerable effort. Ok so based on the magma expansion the volume difference is modest.

 

Are the elements and or molecules which prefer to be gaseous at those temperatures, which will bolster the Earths internal pressures, likely to contribute much by way of Earth volume expansion do you think? I ask this question with no prior personal opinion on the subject. I know nothing of these matters.

 

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Thank you for going to some considerable effort. Ok so based on the magma expansion the volume difference is modest.

 

Are the elements and or molecules which prefer to be gaseous at those temperatures, which will bolster the Earths internal pressures, likely to contribute much by way of Earth volume expansion do you think? I ask this question with no prior personal opinion on the subject. I know nothing of these matters.

 

You were asking originally about cooling so the movement is contraction rather than expansion of the terrestrial part. I have not read the thread from the beginning to really understand your question sorry.

 

Any thought of volume expansion would obviously come from the heating of the Earth's interior.

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if we looked up coefficient of expansion for magma maybe we would get some idea. What would the average temperature of the Earth be?

found one site Thermal expansion coefficient of the magma

5·0 × 10^−5/°C http://petrology.oxfordjournals.org/content/48/7/1295/T3.expansion

The mantle is not molten, so the magma datum is irrelevant.

You would need to take some account of the molten and solid iron nickel core.

I suspect mineral phase changes could have a significant volume effect.

 

Too much work to answer a question that seems to lack significance.

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The mantle is not molten, so the magma datum is irrelevant.

You would need to take some account of the molten and solid iron nickel core.

I suspect mineral phase changes could have a significant volume effect.

 

Too much work to answer a question that seems to lack significance.

As you say it is a lot of work. Now that you mention phase changes, the Outer Core has a considerable volume and is currently liquid.

I'll have to stop thinking of the Mantle as a liquid. Wikipedia on the Mantle says "The mantle is solid but acts like a very viscous liquid over geological time". Wikipedia: https://en.wikipedia.org/wiki/Mantle_(geology)

 

In the mantle, temperatures range between 500 to 900 °C (932 to 1,652 °F) at the upper boundary with the crust; to over 4,000 °C (7,230 °F) at the boundary with the core.[34] Although the higher temperatures far exceed the melting points of the mantle rocks at the surface (about 1200 °C for representative peridotite), the mantle is almost exclusively solid.[34] The enormous lithostatic pressure exerted on the mantle prevents melting, because the temperature at which melting begins (the solidus) increases with pressure.

So at least the temperature range I worked with seems about right. I wonder if the expansion coefficient can be found somewhere?

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As you say it is a lot of work. Now that you mention phase changes, the Outer Core has a considerable volume and is currently liquid.

I'll have to stop thinking of the Mantle as a liquid. Wikipedia on the Mantle says "The mantle is solid but acts like a very viscous liquid over geological time". Wikipedia: https://en.wikipedia.org/wiki/Mantle_(geology)

So at least the temperature range I worked with seems about right. I wonder if the expansion coefficient can be found somewhere?

 

Hi Rob, I have ran this model repeatedly over in my mind for a few years now and have imagined various sticky or viscous materials that we all have probably encountered as possible proxies to simulate the mantle and its reluctance to be moved radially outward. Would cold taffy work? A big ball of cold bubble gum or asphalt tar? They may furnish the viscosity but the gravitational driven restoration of the material is missing, the mantle will eventually move inward towards the core and this gravitationally derived movement and pressure needs to be simulated also.

 

The mantle's thickness is also a major contributor in this mechanism, it provides a type of mechanical increase in proportion to the difference in radius of the lower and upper boundaries.

 

As an example; if we had two hollow spheres that were made of a very hard but resilient material, both with the same outer radius' but with one having a wall thickness three or four times greater than the other. Next, if the two spheres were then hydraulically displaced outward at the same degree beyond the thicker sphere's material's resiliency, the thicker material would experience not only substantially greater outer surface tension but the material inside would experience greater strain energy levels in proportion to their distance from the center. The displacement is similar to the inverse square formula, in this case the strain energy, that resembles in the mantle material a radial strain tension increasing proportionally to the distance from the sphere's center.

 

The displacement could exceed the thicker material's resiliency to the point of structural separation and tearing of the surface while the thinner walled sphere would have encountered no surface damage and lower degrees of internal strain. The accompanying thermal heating that would have been produced in both spheres would have been in greater proportions within the thicker walled example.

 

The mantle's viscosity makes for an interesting puzzle to deconstruct. It is a very hot, sticky and rocky material under extreme pressure. The supposedly cooler mantle material nearer the surface would have less gravitational derived pressures and I would assume higher viscosities than hotter materials farther below, yet, due to the displacement mechanism the upper mantle would be subjected to greater strain energies. While the lower mantle has greater pressures and higher temperatures, I would suppose it would have lower viscosities due to the higher temperatures, but experiences lower displacement metrics and stain energy levels. It is quite overwhelming for someone of my humble abilities and intellect to even begin to figure out how to calculate these values.

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Hi Rob, I have ran this model repeatedly over in my mind for a few years now and have imagined various sticky or viscous materials that we all have probably encountered as possible proxies to simulate the mantle and its reluctance to be moved radially outward. Would cold taffy work? A big ball of cold bubble gum or asphalt tar? They may furnish the viscosity but the gravitational driven restoration of the material is missing, the mantle will eventually move inward towards the core and this gravitationally derived movement and pressure needs to be simulated also.

 

The mantle's thickness is also a major contributor in this mechanism, it provides a type of mechanical increase in proportion to the difference in radius of the lower and upper boundaries.

 

As an example; if we had two hollow spheres that were made of a very hard but resilient material, both with the same outer radius' but with one having a wall thickness three or four times greater than the other. Next, if the two spheres were then hydraulically displaced outward at the same degree beyond the thicker sphere's material's resiliency, the thicker material would experience not only substantially greater outer surface tension but the material inside would experience greater strain energy levels in proportion to their distance from the center. The displacement is similar to the inverse square formula, in this case the strain energy, that resembles in the mantle material a radial strain tension increasing proportionally to the distance from the sphere's center.

 

The displacement could exceed the thicker material's resiliency to the point of structural separation and tearing of the surface while the thinner walled sphere would have encountered no surface damage and lower degrees of internal strain. The accompanying thermal heating that would have been produced in both spheres would have been in greater proportions within the thicker walled example.

 

The mantle's viscosity makes for an interesting puzzle to deconstruct. It is a very hot, sticky and rocky material under extreme pressure. The supposedly cooler mantle material nearer the surface would have less gravitational derived pressures and I would assume higher viscosities than hotter materials farther below, yet, due to the displacement mechanism the upper mantle would be subjected to greater strain energies. While the lower mantle has greater pressures and higher temperatures, I would suppose it would have lower viscosities due to the higher temperatures, but experiences lower displacement metrics and stain energy levels. It is quite overwhelming for someone of my humble abilities and intellect to even begin to figure out how to calculate these values.

I'll have to read the thread from the beginning to get to understand your idea.

It is just that I have quite a bit on my plate at the moment. Sorry I can't comment at the moment.

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My apologies billiards that I did not directly answer your question. Maybe 500 km from min to max over 5-10 million years. Your question is difficult to answer because it is difficult to determine. You would like hard numbers and I do not have them.

 

This explanation below is for anyone who would like more information.

I believe the compression in the crust that produces the mountain ranges such as the Himalayas would give your best chance at an accurate figure. If you were to flatten out all mountain ranges that occurred during the last 10 million years it would give you a divergent boundary infill that occurred during the preceding large thermal increase, minus the unknown subduction values that occurred concurrently.

 

This process is not unlike a mechanical jack place on soft ground, you jack up a few inches and return to find it lower than where you started. I have only observed and reinterpreted what is already known and available. The Basin and range extension is estimated to have had possibly a 100% extension.

 

According to Wikipedia; http://en.wikipedia.org/wiki/Basin_and_Range_Province

 

Total lateral displacement in the Basin and Range varies from 60 – 300 km since the onset of extension in the Early Miocene with the southern portion of the province representing a greater degree of displacement than the north.

 

This could give a rough estimate for the movement in the Pacific divergent plate boundary that was directly beneath and which provided the traction mechanism to pull the Basin and Range during the displacement. The Atlantic would have been in the same proportion to the Pacific divergent boundary as it is now, let's just say its 1/3 of the 300 km, so 100 km for the Atlantic divergent boundary. Now you need the total stretch imposed on all plates and the other divergent plate boundary metrics. I believe the Basin and Range ended prematurely and the thermal displacement continued on further. It could have been as much as another 100 km or more.

 

So, the total could be as great as 500 km. But here's the rub, this process is interrupted repeatedly by the outer core contracting and imposing compression in the crust which produces subduction and reduction of circumference. You could see a gain 25 km and then a loss of 30. Where do you measure from? This is not like a balloon, going up a lot and then back down. Its like running on a conveyor, you may move ahead a little or move back the same, but your gains and losses are smoothed out over the distance covered.

.

Based on the work we did recently this variation in the Earth's radius seems too excessive if you are talking about a fraction of a degree change in internal temperature change.

3000 degree alters the volume of the Earth by 0.15% so the radius change is a cube root of that change.

If my calculations are correct the Earth's radius will only change by 11 meters for every 1 degree change in internal temperature.

Edited by Robittybob1

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Rob, that post is quite old and much has been found in newer supporting evidence.



http://www.researchg...ure_423_499-505


"A 20-Myr record of creation of oceanic lithosphere at a segment of the central Mid-Atlantic-Ridge is exposed along an uplifted sliver of lithosphere. The degree of melting of the mantle that is upwelling below the ridge, estimated from the chemistry of the exposed mantle rocks, as well as crustal thickness inferred from gravity measurements, show oscillations of ,3–4 Myr superimposed on a longer-term steady increase with time. The time lag between oscillations of mantle melting and crustal thickness indicates that the solid mantle is upwelling at an average rate of ,25mmyr, but this appears to vary through time."



"the solid mantle is upwelling at an average rate of ,25mmyr"



It is remarkable that such accurate metrics are available of the mantle's displacement. The movement they impose on the the crust can be seen in the image below.



"show oscillations of ,3–4 Myr superimposed on a longer-term steady increase with time."



post-88603-0-58723200-1453350605_thumb.jpg



The distance between the pause and formation of the caldera indicate the total movement that is imposed by the divergent boundary infill when the mantle moves downward, the resulting GPE in the crust leverages the N. American continent westward as it and its attached oceanic plate move to a lower energy state.



This very accurate set of observations should allow the core's thermal expansion to be calculated once an accurate model of the mantle's displacement is understood. As I said earlier, the mantle produces a mechanical increase in its surface area along with thermal expansion of its entirety from proportional strain energy release. This is largely due to the thickness of the mantle and its response to the displacement when the core thermally expands and initiates the outward mantle movement.



Taking the known metrics and working backwards would seem to me to be the best approach.

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Rob, that post is quite old and much has been found in newer supporting evidence. .

 

It might have been old but it seems so wrong I thought I'd better comment then and there as I work my way through the thread.

Upwelling of the Mantle and the increase in the radius of the Earth are entirely different measurements.

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It might have been old but it seems so wrong I thought I'd better comment then and there as I work my way through the thread.

Upwelling of the Mantle and the increase in the radius of the Earth are entirely different measurements.

 

The model has really started to come together in the last year. Good predictions and a nice fit to plate tectonics.

I think you should read more about it so you can get a better understanding of the mechanism and the surface movement. The "increase in radius" is not what you probably are imagining it is. The crust is gaining and dispersing gravitational potential energy to move the crust into convergent boundaries. A small noticeable increase in radius as the phenomena cycles. The movement of the Yellowstone caldera is a nice representation.

 

But check out post 426, these were cycles that made a significant enough vertical movement in the crustal margins that it left traces in sedimentary rock layers. The paper is below and describes a 554 million year record of the periodic outward and inward displacement of the earth’s crust. The paper shows that the 56 known cycle periods varied between 5 and 15 million years with the average being 10 Ma.

 

http://www.geoconven...c_Tectonics.pdf

Episodic Tectonics in the Phanerozoic Succession of the North American Arctic and the “10 Million Year Flood”

Ashton Embry, Geological Survey of Canada, Calgary, aembry@nrcan.gc.ca

Benoit Beauchamp, University of Calgary, Calgary, bbeaucha@ucalgary.ca

Keith Dewing, Geological Survey of Canada, Calgary, kdewing@nrcan.gc.ca

James Dixon, Geological Survey of Canada, Calgary, jdixon@nrcan.gc.ca

Conclusions

“Fifty-six, large magnitude sequence boundaries have been delineated in the Phanerozoic succession of Arctic North America. The characteristics of the boundaries indicate that they were primarily generated by tectonics. The boundaries occur with an approximate 10 million year frequency (9.8 +/- 3.1). Each boundary was generated during a tectonic episode interpreted to reflect a mantle-driven, plate tectonic reorganization and consequent changes in regional stress fields. Such episodes likely lasted for a few million years and were separated by longer intervals of relative tectonic quiescence. There are indications that the recognized tectonic episodes affected basins throughout the world.”

“A given tectonic episode began with the initial uplift of the basin margin (start of base level fall) and ended with the collapse and marine flooding of the margin (maximum flooding surface). The sequence boundary was generated during the tectonic episode and represents the time of maximum uplift and basinward extent of the unconformity.”

So those two previous research papers confirm the crust is being moved upwards, one metric of the mantle states by 25mm a year.

"the solid mantle is upwelling at an average rate of ,25mmyr"

Solid mantle, not melt, or magma but solid mantle material.

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.....

So those two previous research papers confirm the crust is being moved upwards, one metric of the mantle states by 25mm a year.

"the solid mantle is upwelling at an average rate of ,25mmyr"

Solid mantle, not melt, or magma but solid mantle material.

What I was wanting from you is your understanding of the words "the solid mantle is upwelling at an average rate of ,25mmyr" does that imply to you a global Earth expansion (i.e as a result of a thermal expansion period affecting the entire Earth's mantle or just some local effect at some specific locations, e.g a specific caldera?

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What I was wanting from you is your understanding of the words "the solid mantle is upwelling at an average rate of ,25mmyr" does that imply to you a global Earth expansion (i.e as a result of a thermal expansion period affecting the entire Earth's mantle or just some local effect at some specific locations, e.g a specific caldera?

 

Did you go to the site and read the article?

 

http://www.researchgate.net/publication/10736864_Bonatti_E._et_al._Mantle_thermal_pulses_below_the_Mid-Atlantic_Ridge_and_temporal_variations_in_the_formation_of_oceanic_lithosphere._Nature_423_499-505

http://www.scienceforums.net/topic/73730-plate-tectonic-mechanism/page-22#entry891454

 

"A 20-Myr record of creation of oceanic lithosphere at a segment of the central Mid-Atlantic-Ridge is exposed along an uplifted sliver of lithosphere. The degree of melting of the mantle that is upwelling below the ridge, estimated from the chemistry of the exposed mantle rocks, as well as crustal thickness inferred from gravity measurements, show oscillations of,3–4 Myr superimposed on a longer-term steady increase with time. The time lag between oscillations of mantle melting and crustal thickness indicates that the solid mantle is upwelling at an average rate of,25 mm yr, but this appears to vary through time. Slow-spreading lithosphere seems to form through dynamic pulses of mantle upwelling and melting, leading not only to along-axis segmentation but also to across-axis structural variability. Also, the central Mid-Atlantic Ridge appears to have become steadily hotter over the past 20 Myr, possibly owing to north–south mantle flow."

 

 

"Slow-spreading lithosphere seems to form through dynamic pulses of mantle upwelling and melting"

 

I interpret this to mean they believe there is a distinct difference between the mantle upwelling and the process of melting that occurs when the material decompresses.

 

Apparently, as I understand it, the pressure is so great in the mantle that the mantle material cannot melt until it is exposed through some process to a lower pressure state and is then allowed to decompress and then melt as a result.

 

This seems to be reinforced by this statement: "The time lag between oscillations of mantle melting and crustal thickness indicates that the solid mantle is upwelling at an average rate of,25 mm yr,"

 

The mantle is being oscillated at regular intervals by a mechanism that to the standard model is unknown.

 

The mantle displacement mechanism in this model produces during the above mentioned oscillations mantle surface strain well beyond the material's integrity, causing spontaneous tearing and decompression melting of the surface area. There is evidence of vast layer of magma at the crust-mantle boundary.

 

http://dx.doi.org/10...099.2013.835283

Australian Journal of Earth Sciences: An International Geoscience Journal of the Geological Society of Australia

Volume 60, Issue 6-7, 2013

D. L. Anderson

"Seismology, thermodynamics and classical physics—the physics associated with the names of Fourier, Debye, Born, Gr€uneisen, Kelvin, Rayleigh, Rutherford, Ramberg and Birch—show that ambient shallow mantle under large long-lived plates is hundreds of degrees hotter than in the passive upwellings that fuel the global spreading ridge system, that potential temperatures in mantle below about 200 km generally decrease with depth and that deep mantle low shear wave-speed features are broad, sluggish and dome-like rather than narrow and mantle-plume-like. The surface boundary layer of the mantle is more voluminous and potentially hotter than regions usually considered as sources for intraplate volcanoes."

 

This would suggest there is evidence that the crust/mantle boundary contains large volumes of magma that would be at play in providing a hydraulic medium between the mantle and crust, extending the crust while simultaneously extruding into the divergent boundaries as is currently being observed. The model proposes the magma is dependent on the strain energy that is simultaneously released by the mantle during its displacement.

 

"that potential temperatures in mantle below about 200 km generally decrease with depth"

 

 

That observation runs counter to the the standard model and the generally accepted belief that temperatures are lower nearer to the surface and increase with depth. A source and its accompanying mechanisms would be needed to explain this crust-mantle boundary temperature anomaly.

 

https://www.nsf.gov/news/news_summ.jsp?cntn_id=127315

March 20, 2013

Scientists Discover Layer of Liquefied Molten Rock in Earth's Mantle

Hidden magma layer could play role in shaping the geologic face of our planet

 

"Scientists have discovered a layer of liquified molten rock in Earth's mantle that may be responsible for the sliding motions of the planet's massive tectonic plates." . . . ."The finding may carry far-reaching implications, from understanding basic geologic functions of the planet to new insights into volcanism and earthquakes." . . . ."The scientists discovered the magma layer at the Middle America trench off Nicaragua's shores."

 

"the scientists imaged a 25-kilometer- (15.5-mile-) thick layer of partially melted mantle rock below the edge of the Cocos plate where it moves beneath Central America."

 

"For decades scientists have debated the forces that allow the planet's tectonic plates to slide across the Earth's mantle."

 

""Our data tell us that water can't accommodate the features we are seeing," said Naif. "The information from the new images confirms the idea that there needs to be some amount of melt in the upper mantle. That's what's creating this ductile behavior for plates to slide.""

 

""One of the longer-term implications of our results is that we are going to understand more about the plate boundary, which could lead to a better understanding of earthquakes," said Key.""

 

"The researchers are now trying to find the source that supplies the magma in the newly discovered layer."

 

This model's simple mantle displacement mechanism provides that source of boundary area mantle melt.

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Did you go to the site and read the article?

 

.....

This model's simple mantle displacement mechanism provides that source of boundary area mantle melt.

 

No I didn't read the article for I just want some specific information which relates to your own concepts.

 

From your quote it says "The degree of melting of the mantle that is upwelling below the ridge", so to me that indicates the upwelling is mostly measured below the ridge. That is a local effect and not a global one.

 

Do you agree with that assessment?

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No I didn't read the article

 

Then you are approaching this very broad and lengthy dynamic model from disadvantage.

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Then you are approaching this very broad and lengthy dynamic model from disadvantage.

I am wanting to understand the mechanism of your hypothesis. I started reading that you were proposing that the Earth's Core varied in temperature and this made an expansion and this expansion, and contraction on cooling, results in the continental plates cracking open allowing infill at the mid-ocean ridges, and then on contraction subduction.

The above to my current understanding depends on a global expansion and contraction of the Mantle.

 

Whereas the original Tectonic plate movements were more a result of convection flows in the Mantle.

OK these are simple unrefined concepts.

All I want to know is which one does your idea depend on mostly?

It is possible both depend on Core heating.

Edited by Robittybob1

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Arc - I have had a look at the Bonatti et al, article you often refer to and there are diagrams (fig.5) clearly showing these rates are localized upwelling of solid mantle from the melt zone.

I thought your theory needed a more global expansion of the mantle.

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I am wanting to understand the mechanism of your hypothesis. I started reading that you were proposing that the Earth's Core varied in temperature and this made an expansion and this expansion, and contraction on cooling, results in the continental plates cracking open allowing infill at the mid-ocean ridges, and then on contraction subduction.

The above to my current understanding depends on a global expansion and contraction of the Mantle.

 

Whereas the original Tectonic plate movements were more a result of convection flows in the Mantle.

OK these are simple unrefined concepts.

All I want to know is which one does your idea depend on mostly?

It is possible both depend on Core heating.

 

Arc - I have had a look at the Bonatti et al, article you often refer to and there are diagrams (fig.5) clearly showing these rates are localized upwelling of solid mantle from the melt zone.

I thought your theory needed a more global expansion of the mantle.

 

Hi Rob, have you not read any of the last several pages of this thread? Do I have to repost what has been already argued and supported in conversations in the last three pages?

 

I do not believe the current standard model of mantle convection is a realistic solution to solve the almost cryptic history of this planet's surface. The reason for mantle convection being the long sought viable solution for this planet’s surface is simple, there were not any other viable alternatives.

 

http://www.researchg...ure_423_499-505

 

"A 20-Myr record of creation of oceanic lithosphere at a segment of the central Mid-Atlantic-Ridge is exposed along an uplifted sliver of lithosphere. The degree of melting of the mantle that is upwelling below the ridge, estimated from the chemistry of the exposed mantle rocks, as well as crustal thickness inferred from gravity measurements, show oscillations of ,3–4 Myr superimposed on a longer-term steady increase with time. The time lag between oscillations of mantle melting and crustal thickness indicates that the solid mantle is upwelling at an average rate of ,25mmyr, but this appears to vary through time."

 

The number of predictions of observations that can be generated by this paragraph is remarkable. The 3-4 million year oscillations match the periodic movement of the N. American continent over the Yellowstone complex that lies below it, and the Pacific Plate’s periodic movement over the Hawaiian hotspot are just a few and when combined with other research papers make a very robust argument, such as in post 422 and 426 on page 22. . . . . . . please don't make me repost or, worse yet re argue the same points.

 

When I first posted the Bonatti et al research paper above I was in the middle of a rather contentious debate on a prediction about the Atlantic MOR. That paper with several others solidified the cause and effect to make the Bonatti et al observation a piece in a series of causes and effects.

 

The oscillations can be shown that they are a globally synchronized crustal movement by the Bonatti et al paper and this one below.

 

http://www.geoconven...c_Tectonics.pdf

 

Episodic Tectonics in the Phanerozoic Succession of the North American Arctic and the “10 Million Year Flood”

Ashton Embry, Geological Survey of Canada, Calgary, aembry@nrcan.gc.ca

Benoit Beauchamp, University of Calgary, Calgary, bbeaucha@ucalgary.ca

Keith Dewing, Geological Survey of Canada, Calgary, kdewing@nrcan.gc.ca

James Dixon, Geological Survey of Canada, Calgary, jdixon@nrcan.gc.ca

 

Conclusions

“Fifty-six, large magnitude sequence boundaries have been delineated in the Phanerozoic succession of Arctic North America. The characteristics of the boundaries indicate that they were primarily generated by tectonics. The boundaries occur with an approximate 10 million year frequency (9.8 +/- 3.1). Each boundary was generated during a tectonic episode interpreted to reflect a mantle-driven, plate tectonic reorganization and consequent changes in regional stress fields. Such episodes likely lasted for a few million years and were separated by longer intervals of relative tectonic quiescence. There are indications that the recognized tectonic episodes affected basins throughout the world.”

 

“A given tectonic episode began with the initial uplift of the basin margin (start of base level fall) and ended with the collapse and marine flooding of the margin (maximum flooding surface). The sequence boundary was generated during the tectonic episode and represents the time of maximum uplift and basin ward extent of the unconformity.”

 

So those two previous research papers confirm the crust is being globally moved upwards and would suggest they are in synchronized time periods, one metric of the mantle states by 25mm a year.

 

"the solid mantle is upwelling at an average rate of ,25mmyr"

 

This thread has been down this road already. If you read the last 4 pages you may save a lot of repetition in post content. In fact, I would start at post 348 on page 18, that would bring you up to date and save a lot of time and trouble.

Edited by arc

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....

 

So those two previous research papers confirm the crust is being globally moved upwards and would suggest they are in synchronized time periods, one metric of the mantle states by 25mm a year.

 

"the solid mantle is upwelling at an average rate of ,25mmyr"

 

This thread has been down this road already. If you read the last 4 pages you may save a lot of repetition in post content. In fact, I would start at post 348 on page 18, that would bring you up to date and save a lot of time and trouble.

So you are using an obvious local measurement and suggesting that the rate has some bearing to the global effect.

Surely you are not suggesting that rate is the global rate!

 

I'm not wanting you to prove anything. I just want you to describe the basic principles behind your hypothesis, the ones you have stuck with up to this stage.

Please can you be as brief as possible.

 

Are you still needing a oscillating temperatures of the Earth's inner parts?

Have you been able to link this to the Earth's magnetic field?

Edited by Robittybob1

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So you are using an obvious local measurement and suggesting that the rate has some bearing to the global effect.

Surely you are not suggesting that rate is the global rate!

 

I'm not wanting you to prove anything. I just want you to describe the basic principles behind your hypothesis, the ones you have stuck with up to this stage.

Please can you be as brief as possible.

 

Are you still needing a oscillating temperatures of the Earth's inner parts?

Have you been able to link this to the Earth's magnetic field?

 

He found a paper with the word "oscillation" and "mantle" in and then completely bastardised it. This is the quality of science we are having to deal with here.

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