[seahorse3]

Someone posted this video elsewhere taking the position that geology says the earth is growing over time. I don't know enough to know, but found it interesting. Hopefully Rockdoc and others can view and make comments. I've never heard this idea before.http://www.youtube.com/watch?v=oJfBSc6e7QQ

[dolanbaker]

Just looked at the video, the first question that jumps out is "where did all the sea water come from to fill in the oceans?"
Did it just appear like magic!

[Plantagenet]

"where did all the sea water come from to fill in the oceans?"
Did it just appear like magic!

No. The earth is not expanding.

This is a curious idea from the 19th century that can be easily disproved using modern geophysical data on plate motions and subduction rates.

The earth has had oceans for billions of years. Some of the water in the oceans outgassed from the earth as it cooled after planetary accretion. Other parts of it may have accumulated from comet impacts on the earth.



Cheers!

[peeker01]

I've got a better question.......86 million barrels of crude being turned into heat, energy and
co2, every day. A major percentage of this mass escapes into space. Is our orbit changing due to the decreasing mass of the earth? Anybody? 86M x30x6x365=56 trillion pounds +- every year, of course decreasing backwards in time, but it is still alot of angular momentum being lost. No?

[The Practician]

I've got a better question.......86 million barrels of crude being turned into heat, energy and
co2, every day. A major percentage of this mass escapes into space. Is our orbit changing due to the decreasing mass of the earth? Anybody? 86M x30x6x365=56 trillion pounds +- every year, of course decreasing backwards in time, but it is still alot of angular momentum being lost. No?

From wikipedia on atmospheric loss:

Earth is too large to lose particles efficiently through Jeans Escape.[dubious – discuss] The exosphere is the high altitude region where atmospheric density is sparse and Jeans Escape occurs. Jeans escape calculations assuming an exosphere temperature of 1,800 degrees show that to deplete O+ ions by a factor of e (2.78...) would take nearly a billion years. 1,800 degrees is higher than the actual observed exosphere temperature; at the actual average exosphere temperature, depletion of O+ ions would not occur even over a trillion years. Furthermore, most oxygen on Earth is bound as O2, which is too massive to escape Earth by Jeans Escape.[citation needed]

Earth’s magnetic field protects it from solar winds and prevents escape of ions, except along open field lines at the magnetic poles. The gravitational attraction of Earth’s mass prevents other non-thermal loss processes from appreciably depleting the atmosphere. Yet Earth’s atmosphere is two orders of magnitude less dense than that of Venus at the surface. Because of the temperature regime of Earth, CO2 and H2O are sequestered in the hydrosphere and lithosphere. H2O vapor is sequestered as liquid H2O in oceans, greatly decreasing the atmospheric density. With liquid water running over the surface of Earth, CO2 can be drawn down from the atmosphere and sequestered in sedimentary rocks. Some estimates indicate that nearly all carbon on Earth is contained in sedimentary rocks, with the atmospheric portion being approximately 1/250,000 of Earth’s CO2 reservoir.[citation needed] If both of the reservoirs were released to the atmosphere, Earth’s atmosphere would be denser than even Venus’s atmosphere. Therefore, the dominant “loss” mechanism of Earth’s atmosphere is not escape to space, but sequestration.

so now you can sleep easy at night knowing all that heat, energy and C02 isn't being lost into space. In fact, all that extra CO2 we're burning is working to keep the heat -- which isn't particularly heavy by the way-- in.

[peeker01]

Hmmmm.....I read that three times and I am not sure it is talking about heat and energy.

[The Practician]

Hmmmm.....I read that three times and I am not sure it is talking about heat and energy.

Then why don't you go put some heat energy on your bathroom scale and tell me what it reads.

[Sixstrings]

A planet is a closed system as far as mass goes. It cannot grow.

Except situations like how our moon formed, after a planet collided with the early Earth and a big molten blob plopped out and our moon formed from the debris.. the net effect probably added mass to the Earth, since scientists believe it was a Mars-sized planet that hit us and the Moon isn't Mars-sized so the extra mass went somewhere..

[peeker01]

No strings, my question is one of mass reduction, not growth.

[The Practician]

No strings, my question is one of mass reduction, not growth.

What, are you a gravity skeptic too? Please, just go type "what does energy weigh?" at askjeeves.com or something and leave the adults alone!

[The Practician]

No strings, my question is one of mass reduction, not growth.

What, are you a gravity skeptic too? Please, just go type "what does energy weigh?" at askjeeves.com or something and leave the adults alone!

Welcome to peak oil Practician.

I've been lurkin here a while.

[Oakley]

The gravitational force at the surface of the earth places a limit on the size of land animals with elephants being the largest today. Elephants are significantly smaller than the largest known dinosaurs of 65 million years ago, which were huge by comparison; these dinosaurs could not possible have lived if the gravity was the same or greater back 65 million years ago. Their massive bodies could not have been supported by their bone structure. The logical conclusion is that gravity was less 65 million years ago.

Could this fit in with the idea that the earth had half the diameter 65 million years ago as Neal Adams suggests? It could if you assume that as the earth doubled in diameter since then it also increased mass in proportion to its new volume as calculated using its new diameter plugged into the simple formulas for the volume of a sphere. If you go back in time 65 million years, shrinking the diameter by 1/2 then the volume would shrink by 1/8, and if the mass decreases by 1/8 also, then surface gravity would have been 1/2 of what it is today. This is interesting because if the mass 65 million years ago and the mass today did not change, but the diameter increased, then surface gravity back then would have actually been 4 times what it is today, making it even more impossible for dinosaurs to have existed at the sizes their fossils show was the case.

So the size of the dinosaurs suggest that Neal Adam's idea of an expanding earth has validity. It also suggests then that the earth's mass does increase with its diameter, and that surface gravity increases by a factor of 2 when the diameter doubles. This opens a whole set of questions about how the additional mass gets here, and it also suggests that if the growth continues, eventually gravity will become overwhelming for all but the smallest land animals here on earth.

Neal Adams presents additional visual evidence using other planets and moons at this site and also details some of his arguments at the bottom of that page:

http://www.nealadams.com/nmu.html

[dolanbaker]

"where did all the sea water come from to fill in the oceans?"
Did it just appear like magic!

No. The earth is not expanding.

This is a curious idea from the 19th century that can be easily disproved using modern geophysical data on plate motions and subduction rates.


Cheers!

Exactly, It's the daftest idea I've heard since the theory that the sun went around the Earth.

[seahorse3]

I was curious about certain "facts" put forth in the video, to see if those are in fact "facts." The video states as fact that all the continents, including the poles, fit perfectly together. Is that true? The video then states as fact that the sea floor is 70 millions years old while the continental land masses are over 100 million years old, thus implying the earth is expanding. Is it fact that the sea floor is much younger than the continents? It states the gorge marks on the ocean floor point direction of movement (east and west). True? The video states that certain forest in the upper continents are all of the same type, even though now separated by oceans and that remnants of those forest have been found in the north pole (I believe it said). Is that a fact?

[steam_cannon]

Peak Oil is a blog about geology and economics. Not hokum flat earth, hollow earth or earth is growing BS.

No. The earth is not expanding.

This is a curious idea from the 19th century that can be easily disproved using modern geophysical data on plate motions and subduction rates.

The earth has had oceans for billions of years. Some of the water in the oceans outgassed from the earth as it cooled after planetary accretion. Other parts of it may have accumulated from comet impacts on the earth.

Correct.

The gravitational force at the surface of the earth places a limit on the size of land animals with elephants being the largest today. Elephants are significantly smaller than the largest known dinosaurs of 65 million years ago, which were huge by comparison; these dinosaurs could not possible have lived if the gravity...

All completely wrong.

There are pretty much two factors that effected dinosaur size and gravity is not one. Genetics between comet impact and oxygen levels in the atmosphere. Birds still possess the ability to grow a similar skeletal structure, so genetics is not the limiting factor. But oxygen levels is a limiting factor. Insects like the dragon fly are perhaps the clearest example. The ancient dragon flies were close to five feet wide, but they cannot get that big in current atmospheric conditions and neither can most insects. Insects use a lung system which too inefficient at low oxygen concentrations like we have today. At 20% oxygen levels, even lung type respiratory systems are too inefficient for anything much larger then an elephant.

High Oxygen Levels Spawn Super-sized Dragonflies (Proven 2010)

Biologists and Palaeobiologists have been working on an extensive project to assess oxygen concentrations on the effect of insect growth. The team have managed to produce super-sized dragonflies, ones which are 15% bigger than normal by raising the insects in chambers that imitate Earth's high oxygen concentrations during the Carboniferous.

The atmosphere's composition during the Mesozoic was vastly different as well. Carbon dioxide levels were up to 12 times higher than today's levels, and oxygen formed 32 to 35% of the atmosphere,[citation needed] as compared to 21% today. However, by the late Cretaceous, the environment was changing dramatically. Volcanic activity was decreasing, which led to a cooling trend as levels of atmospheric carbon dioxide dropped. Oxygen levels in the atmosphere also started to fluctuate and would ultimately fall considerably. Some scientists hypothesize that climate change, combined with lower oxygen levels, might have led directly to the demise of many species. If the dinosaurs had respiratory systems similar to those commonly found in modern birds, it may have been particularly difficult for them to cope with reduced respiratory efficiency, given the enormous oxygen demands of their very large bodies.[6]

[Pops]

Peak Oil is a blog about geology and economics. Not hokum flat earth, hollow earth or earth is growing BS.

Take a pill:

The Open Forum is for other topics that may be of interest or benefit to our members.

[steam_cannon]

Take a pill:

The Open Forum is for other topics that may be of interest or benefit to our members.

Yep and if they post poor quality ideas they are going to openly get knocked down. I know you're responding to my bold text about this being a geology and economics website. Of course we don't need to discuss only Geology or Economics. Personally I think other topics that relate to the community are worth discussing. But tinfoil hat topics like the old "out of this world" section took away from the forums quality and the subject of peak oil in general which has had a lot of good research go into it. So I'm glad the "out of this world" section is gone and I'd rather the open discussion section doesn't turn into the same thing. Tinfoil science is bad science and conspiracy talk makes me itch.

[seahorse3]

Well, I'm still interested in verifying the "facts" put forth in the video that I posted earlier. The benefit of forums like this is people with vast experience and knowledge in particular areas. I'm not even close to a geologist, so, I would hope that some of our resident geologist would indulge me for a second here. There are many things I find interesting for fun.

[Oakley]

Yep and if they post poor quality ideas they are going to openly get knocked down. I know you're responding to my bold text about this being a geology and economics website. Of course we don't need to discuss only Geology or Economics. Personally I think other topics that relate to the community are worth discussing. But tinfoil hat topics like the old "out of this world" section took away from the forums quality and the subject of peak oil in general which has had a lot of good research go into it. So I'm glad the "out of this world" section is gone and I'd rather the open discussion section doesn't turn into the same thing. Tinfoil science is bad science and conspiracy talk makes me itch.

Perhaps the world is more complex than your single minded attribution of dinosaur size to higher oxygen levels alone. I say single explanation because the second explanation you offer, genetics, simply begs the question and is not an answer at all; genetics is simply the means through which their size is transmitted from generation to generation. I seriously doubt that oxygen alone would explain why the largest land animal today is 7 tons while some of the dinosaurs were estimated to be 90 tons. Bone and muscle have limitations which place limitations on size; what those limitations are is better left to the minds of those who study kinesiology and paleontology.

Often it helps to understand things better to think of extremes. What do you think land animals would look like on a planet with 50 or 100 times the gravity of earth? Do you think that even in an environment more rich in oxygen that such creatures even the size of elephants, much less dinosaurs, could exist under those surface gravity conditions? I think your dismissal of gravity as a possible factor defies logic.