Robert, I figured you were trying to stoke an interesting conversation. I like a good challenge to what I see as current understanding. I know our "facts" are always subject to change :) Plate Tectonics actually does exist on Europa, but it's mantle is liquid water, and its plates are ice. I think I remember my astro 101 teacher saying something about the Valis Marineris. He mentioned a theory about Olympus Mons causing uneven stress on the crust and "ripping" apart the valis Marineris. I don't know if I buy that or not. One of my friends pointed out it looks like a "grazing impact" from a meteor, and I think I found a site where someone theorized about an asteroid like moon in retrograde orbit smashing into mars at a low angle. Its been shot down by anyone I've brought it up to. I remember learning that Mars didn't have the mass to retain its internal heat like the earth has. Maybe this lack of mass and heat never really got enough convection going int he mantle of mars to cause a crust thin enough to break up and move around? On the flip side, if the earth expanded, and mars is so similar, why wouldn't we see the exact same evidence he is claiming exists here, on mars? I agree that a lot of breakthroughs come from the fringes, at some point, big steps are made though. I really think the expanding earth theory doesn't explain much of what is observed. The guy states that the lithosphere is riding around on the oceanic crust. This is not true. At some point the oceanic crust gets thrust down deep into the mantle and is totally recycled. The Atlantic and pacific ocean basins are not "meeting up" under the Americas. Some part of the lithosphere sits on or very near the mantle. The ocean floors are made up of young rock because the rock is being generated at the mid ocean ridges. It spreads on the order of cm a year. It wouldn't then last for billions of years between continents before being recycled back into the mantle at an active margin. There are also differential rates observed in different ocean basins. This is all probably a byproduct of a dynamic mantle. An interesting note. The mid ocean ridges are huge mountains. As the fresh magma rises and goes through a process of adiabatic decompression, it starts out very buoyant and not as dense as it gets as it cools off. This is why the ranges are there, and as you move from them, they taper off. This process is only a function of the temperature though, so if the rates the ridge is making new crust increase, the mid ocean ridge ranges get wider. This displaces more water, and also increases volcanic activity at the active plate margins. The effect is higher ocean levels and more CO2 in the atmosphere. Sounds a lot like what the late cretaceous was like. David On 1/14/2011 6:52 PM, Robert Taylor wrote:
Thanks David, I enjoyed reading that.
A part II on this and perhaps what I find more fascinating is that this theory seems to explain aspects of Lunar and Martian geology that can't be explained by Plate Tectonics, because there isn't any there.
Valis Marineris has always bothered me. I never liked the water theory as the valley is just far too wide to have been caused by water. If you haven't looked at the Adam's videos that refer to Mars and the Moon from the original post's link I invite you look at them, if nothing else they are a different way to explain them.
Also I don't like that we have expansion joints in both the Pacific and Atlantic Oceans that appear to expand into each other, and why are the Ocean floors made up of such young rocks? They should be much older if in fact the continents have been drifting for as long as the Plate Tectonics Theory would have us believe. We have rocks on land that are Billions of years old, yet right off shore they are no older than 125 million, does that make sense? Subduction should provide a more even transition in the age of rocks. Certainly the Pacific Ocean's floor should be much older than the Atlantic Oceans floor, but it's not. I am still lost as to why we didn't figure out the South America and Africa fit together until about 70 years ago, every school child knew it, hmm, our maps weren't that bad in the 40s and 50s. Plate Techtonics is still a very young science.
http://geology.about.com/library/bl/maps/blseafloorage.htm
BTW: Adams is not the only person studying the expanding Earth theory, there are others, it is not as fringe as you might think. I personally don't have any issues with the current Plate theories although I try to be open minded. Often the real breakthroughs come from the fringe, ask Galileo, or Einstein, or Hubble who were all ostracized by the mainstream at one point in their careers before they were shown to be correct.
I'm just playing Devil's Advocate, I think it's a fascinating theory and may be correct about a few things, but I'm not a Geologist, although I do know a few if that counts.
Bob
-----Original Message----- From: utah-astronomy-bounces@mailman.xmission.com [mailto:utah-astronomy-bounces@mailman.xmission.com] On Behalf Of David Rankin Sent: Friday, January 14, 2011 5:26 PM To: Utah Astronomy Subject: Re: [Utah-astronomy] Expanding Earth?
Robert:
It is my understanding that gravity can counter-act, and even overcome the expansion. Which is why they theorize that Andromeda and the Milky Way will someday collide even though the space between them is increasing.
I'm bored, might as well.
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