J. Marvin Hearndon sometimes posts papers on arXiv about the formation of the Earth. He thinks that most current geologic theories of planet formation are wrong in some detail or another.

In this paper, he suggests that the reason that the Earth's continents could all fit together on a smaller globe without oceans is that the solid part of the Earth had been compressed by a Jupiter-sized atmosphere. When the atmosphere dissipated, the rocky part of the Earth expanded about 50%. I don't subscribe to his theory [yet], but he makes a fairly easy to read and self-consistent argument. Take a look.

Protoplanetary Earth Formation: Further Evidence and Geophysical Implications

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Forming opinions as we speak

A couple of questions - he mentions the age of the ocean floor - 200 million years - but how does his theory tie in with the overall age of the earth/solar system - would it take a humungous amount of time for the process he puts forward to occur?

Can we work out if the age of the earth (best guess) would allow this?

What about all the water?

He says all the hydrogen disappeared from the atmosphere - how does this tie in?

I must admit that though I know nothing at all about this I do like the idea of an expanding earth and it fits with the shape of the continents and all.

Mild

The idea also appeals to me.

However, there is a lot of stuff in the theory which doesn't make sense for his argument. It seems reasonable that the Earth had a lot more hydrogen in the past, since we have seven-times elevated levels of deuterium in our water compared to the sun, Jupiter and the ISM [Venus has 35 times]. but I don't think that we need a Jupiter Mass of hydrogen around the Earth to get that result. But we would need it if all that Hydrogen compressed our stony core by 40%.

You can look up Hearndon's other papers. He's knowledgeable, and has put a lot of thought into them, but there are a few gaps.

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Forming opinions as we speak

On the whole Jovian sized atmosphere boiling off thing -
Wouldn't we observe this elsewhere in the Universe in young planets?
Can we expect Jupiter to start shrinking one day?

Why are neptune and uranus and saturn not turning into earths? It is thought that they have rocky cores but we dont see any evidence of their atmospheres about to blow away.

I have no doubt that some of the processes which he describes are reasonably valid, the idea that iron would rain down into the core of a gaseous proto planet followed by other elements as the body cooled is entirely plausible.

When this is applied to the earth...
The earth bulges and expands as a matter of course, due to the weight of the oceans and crust.

I dont think the continents fit quite so nicely to make such a sweeping statement. The earths surface is in constant turmoil (over geological periods). It is unlikely that we can predict so acurately what early earth continents looked like. I do believe though that the earth had a far larger atmosphere than it has now - at 3.5billion years old I am sure that a great deal of the atmosphere has boiled off.

If the planet was expanding from the mechanism he suggests we should not find any subduction zones. With an expanding crust the continents should be moving away from each other. Even if the expansion had stopped, I dont believe the mechanism for which he attributes the geology of today is adequate.

Interesting read. I am dubious though--he doesn't seem to account for the current activity in the earth's crust, nor the current ongoing movement of the continants in relation to each other.

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All civilizations become either spacefaring or extinct.~ Carl Sagan ~

Humanity must rise above the Earth, to the top of the atmosphere and beyond, for only then will we fully understand the world in which we live.~Socrates, 500 B.C. ~

Let every man judge according to his own standards, by what he has himself read, not by what others tell him. ~Albert Einstein~

Radiometric techniques were used by John Tuzo Wilson from Princeton in 1964
and found that islands that lie close to the Atlantic Ridge are younger than those
closer to each mainland..

The particular rocks along the west coast of Africa match those of South America
in matching locations...

When volcanic rocks cool, they freeze in the orientation of the Earth's magnetic field..Ships have found compass needles flipping back and forth by 180*, suggesting reversals of the field in the past. These magnetic stripes are parallel
and symmetric about the ridge line..

New crust comes up from the Atlantic and heads back into the mantle in the Pacific rim where volcanoes occur frequently..

Read "The Sciences: An Integrated Approach" by Trefil and Hazen

Also,

"Understanding Earth" by Press and Siever

And,

"The Dark Side of Earth" by Wood

blueshift