Freethought & Rationalism Archive

Deathray 6 · 10-01-2002, 09:39 AM

I was recently having a short discussion with someone about geology and I was mentioning subduction zones and mountain building. While I find the evidence in favor of plate tectonics to be way more then sufficient, the person I was talking to said they disagreed with the idea. They said that there were problems with the formation of mountains, such as that discontinuous rates of mountain building are a major flaw of mountain building. They then gave a link to this site: <a href="http://www.ping.be/jvwit/expandingearthobjplatetect.html" target="_blank">http://www.ping.be/jvwit/expandingearthobjplatetect.html</a> . He apparently advocates this "expanding earth" theory as an alternative uniformist theory. It sounds like a novel idea, but it also seems just plain wrong. I have problems with this theory, such as "Why is there no mechanism to make the Earth expand?" among other things. Is there something I can use as a rebuttal to the claims of my discussion partner? This is only one of several recent objections to plate tectonics, and said objections are something totally new to me. Any suggestions?

(notes: If this belongs in the science forum, please move it there. It just seems to me like geology would be a subject more fit for the evolution board. Also, please refrain from the "he's a crackpot, so don't bother with him" arguements that I've heard before when asking for advice about other discussions. I don't believe in such subjective labelling. I just merely want to put my point across,--which in this discussion is that plate tectonics is the better theory--and leave it at that.)

scigirl · 10-01-2002, 10:16 AM

Hello Deathray6, and welcome.

I'll leave it here for now, mainly because I think you'll get good responses. If another mod moves it to S&S, I don't mind tho. . .

scigirl

Coragyps · 10-01-2002, 12:21 PM

From the link:

Quote:

the Himalayas and the Tibetan plateau were uplifted during the last 3.4 million years

Errrm.. I'll check when I get home this evening, but I think there's a decimal misplaced in that 3.4.
And, indeed, how the @#%$&*$ can the Earth be expanding? Yeast, maybe?

Grumpy · 10-01-2002, 01:06 PM

Incidentally, if God decreed that the Earth as He created it was "good," has it become less good due to continents slipping around? Were landmasses fixed until Noah's flood? Or did Adam's Curse set the processes of geology in motion, just as The Fall has also been credited with triggering genetic mutations, carnivory, and supernovae?

Coragyps · 10-01-2002, 01:41 PM

Quote:

just as The Fall has also been credited with triggering genetic mutations, carnivory, and supernovae?

Yeah, that apple-eatin' bitch.....

lpetrich · 10-01-2002, 03:08 PM

What examples does he give of discontinuity in rates of mountain building?

And why is that supposed to be contrary to what one might expect of continental drift?

Coragyps · 10-01-2002, 05:13 PM

The first four sites I found searching "Himalaya orogeny" on Google all gave 45 to 50 million years ago as the start of mountain building over there - so a date of 3.4 Ma sure raises my suspicions of the whole site.

ps418 · 10-01-2002, 05:52 PM

According to sources cited in Condie, paleomagnetic data are not consistent with more than 0.8% earth radius increase since 400Ma, and cratering patterns on the moonrule out more than 0.06% radius increase during the last 4Ga (Plate Tectonics and Crustal Evolution, 1986, p. 13). And Deathray already mentioned the lack of a mechanism to produce expansion, which is an important point. Thermal contraction would seem to work in the oppodite direction.

Regarding mountain-building, how can there be any dispute that plate-plate collisions are capable of forming mountains? We can measure the relative velocities of converging plates (e.g. the convergence of the pacific and Eurasian plates), and the associated uplift of mountain ranges. You can even "see", from seismic data, the outline of subducting plates at converging plate margins (the seismic <a href="http://www.xrefer.com/entry/608443" target="_blank">Benioff zone</a>). Here's an example from the <a href="http://www.gcn.ou.edu/~jahern/v&e/subduct/tonga_bz.gif" target="_blank">Tonga trench.</a>

I'm not sure what it means to say that plate tectonics cannot explain mountain-building, so I must be missing something here.

Deathray 6 · 10-02-2002, 11:46 AM

Eh. I haven't been able to get back with my discussion partner yet, so I can't find out what sources he cites. I did try looking around the net for some more on this "expansion tectonics" theory. I didn't find much, but what I did find was pretty informative on the theory, whose founder is apparently a man by the name of S.W. Carey. The links are at the end of this post. There wasn't much in the way of explanations for a mechanism for expansion. The first site below made a comparison on their opening page between plate boundaries and skull sutures. They also said that Earth was probably about 60% of its present diameter 200 MYA. What would that be, about 7500 km compared to the present 12,750 km? That sounds rather odd, since we know that solids and liquids have a more or less constant specfic gravity. The sp. gr. lessens as the substance is heated, that is it expands, but not much. When a substance is cooled it contracts (unless it crystallizes upon freezing, like ice), thus increasing its sp.gr., but not much at all either. Earth's interior (the core, anyway) is made up mostly of iron, whose sp. gr. is about 7.8. Even after cooling or heating, its sp. gr. should not deviate much from that value. Likewise, even if the Earth were to heat up, it couldn't expand much, definitely not the 4.63 times suggested. No solid or liquid does that much expanding or contracting, and if they ever suggest a gaseous iron interior, well, that is a) rather absurd, b) seems to rule out a dynamo for generating the planet's magnetic field, and c) it would probably cause the above layers to collapse back towards the planet center. The earth's inner core is definitely solid, and its outer core is definitely liquid. This whole expansion tectonics thing just doesn't measure up, and it obviously violates some rather elementary things.

More "Expansion Tectonics" links:

<a href="http://www.expanding-earth.org" target="_blank">http://www.expanding-earth.org</a>

<a href="http://www.geocities.com/CapeCanaveral/Launchpad/8098/1.htm" target="_blank">http://www.geocities.com/CapeCanaveral/Launchpad/8098/1.htm</a>

<a href="http://www.triplehood.com/peex2.htm" target="_blank">http://www.triplehood.com/peex2.htm</a>

Jesus Tap-Dancin' Christ · 10-02-2002, 12:25 PM

Well, a gravity of nearly 40 m/s^2 should be plenty to shut their asses up. Atmospheric pressure would have been huge as well--96 PSI. Would've been damn hard to move, hell, breathe, with that much force bearing down on you.

With a radius of nearly half of what it is today, both those conditions would be true due to the inverse square relationship of gravity.

Don't these people think about THAT kind of shit? Life would not have existed. Period.

10-01-2002, 09:39 AM	#1
Deathray 6 Junior Member Join Date: Nov 2001 Location: Somewhere Posts: 20	Objections to plate tectonics? Huh? I was recently having a short discussion with someone about geology and I was mentioning subduction zones and mountain building. While I find the evidence in favor of plate tectonics to be way more then sufficient, the person I was talking to said they disagreed with the idea. They said that there were problems with the formation of mountains, such as that discontinuous rates of mountain building are a major flaw of mountain building. They then gave a link to this site: <a href="http://www.ping.be/jvwit/expandingearthobjplatetect.html" target="_blank">http://www.ping.be/jvwit/expandingearthobjplatetect.html</a> . He apparently advocates this "expanding earth" theory as an alternative uniformist theory. It sounds like a novel idea, but it also seems just plain wrong. I have problems with this theory, such as "Why is there no mechanism to make the Earth expand?" among other things. Is there something I can use as a rebuttal to the claims of my discussion partner? This is only one of several recent objections to plate tectonics, and said objections are something totally new to me. Any suggestions? (notes: If this belongs in the science forum, please move it there. It just seems to me like geology would be a subject more fit for the evolution board. Also, please refrain from the "he's a crackpot, so don't bother with him" arguements that I've heard before when asking for advice about other discussions. I don't believe in such subjective labelling. I just merely want to put my point across,--which in this discussion is that plate tectonics is the better theory--and leave it at that.)

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10-01-2002, 10:16 AM	#2
scigirl Veteran Member Join Date: Jul 2001 Location: Seattle Posts: 4,261	Hello Deathray6, and welcome. I'll leave it here for now, mainly because I think you'll get good responses. If another mod moves it to S&S, I don't mind tho. . . scigirl

10-01-2002, 01:06 PM	#4
Grumpy Veteran Member Join Date: Jul 2000 Location: Alaska, USA Posts: 1,535	Incidentally, if God decreed that the Earth as He created it was "good," has it become less good due to continents slipping around? Were landmasses fixed until Noah's flood? Or did Adam's Curse set the processes of geology in motion, just as The Fall has also been credited with triggering genetic mutations, carnivory, and supernovae?

10-01-2002, 03:08 PM	#6
lpetrich Contributor Join Date: Jul 2000 Location: Lebanon, OR, USA Posts: 16,829	What examples does he give of discontinuity in rates of mountain building? And why is that supposed to be contrary to what one might expect of continental drift?

10-01-2002, 05:13 PM	#7
Coragyps Veteran Join Date: Aug 2001 Location: Snyder,Texas,USA Posts: 4,411	The first four sites I found searching "Himalaya orogeny" on Google all gave 45 to 50 million years ago as the start of mountain building over there - so a date of 3.4 Ma sure raises my suspicions of the whole site.

10-01-2002, 05:52 PM	#8
ps418 Veteran Member Join Date: Mar 2001 Location: Louisville, KY, USA Posts: 1,840	According to sources cited in Condie, paleomagnetic data are not consistent with more than 0.8% earth radius increase since 400Ma, and cratering patterns on the moonrule out more than 0.06% radius increase during the last 4Ga (Plate Tectonics and Crustal Evolution, 1986, p. 13). And Deathray already mentioned the lack of a mechanism to produce expansion, which is an important point. Thermal contraction would seem to work in the oppodite direction. Regarding mountain-building, how can there be any dispute that plate-plate collisions are capable of forming mountains? We can measure the relative velocities of converging plates (e.g. the convergence of the pacific and Eurasian plates), and the associated uplift of mountain ranges. You can even "see", from seismic data, the outline of subducting plates at converging plate margins (the seismic <a href="http://www.xrefer.com/entry/608443" target="_blank">Benioff zone</a>). Here's an example from the <a href="http://www.gcn.ou.edu/~jahern/v&e/subduct/tonga_bz.gif" target="_blank">Tonga trench.</a> I'm not sure what it means to say that plate tectonics cannot explain mountain-building, so I must be missing something here.

10-02-2002, 11:46 AM	#9
Deathray 6 Junior Member Join Date: Nov 2001 Location: Somewhere Posts: 20	Eh. I haven't been able to get back with my discussion partner yet, so I can't find out what sources he cites. I did try looking around the net for some more on this "expansion tectonics" theory. I didn't find much, but what I did find was pretty informative on the theory, whose founder is apparently a man by the name of S.W. Carey. The links are at the end of this post. There wasn't much in the way of explanations for a mechanism for expansion. The first site below made a comparison on their opening page between plate boundaries and skull sutures. They also said that Earth was probably about 60% of its present diameter 200 MYA. What would that be, about 7500 km compared to the present 12,750 km? That sounds rather odd, since we know that solids and liquids have a more or less constant specfic gravity. The sp. gr. lessens as the substance is heated, that is it expands, but not much. When a substance is cooled it contracts (unless it crystallizes upon freezing, like ice), thus increasing its sp.gr., but not much at all either. Earth's interior (the core, anyway) is made up mostly of iron, whose sp. gr. is about 7.8. Even after cooling or heating, its sp. gr. should not deviate much from that value. Likewise, even if the Earth were to heat up, it couldn't expand much, definitely not the 4.63 times suggested. No solid or liquid does that much expanding or contracting, and if they ever suggest a gaseous iron interior, well, that is a) rather absurd, b) seems to rule out a dynamo for generating the planet's magnetic field, and c) it would probably cause the above layers to collapse back towards the planet center. The earth's inner core is definitely solid, and its outer core is definitely liquid. This whole expansion tectonics thing just doesn't measure up, and it obviously violates some rather elementary things. More "Expansion Tectonics" links: <a href="http://www.expanding-earth.org" target="_blank">http://www.expanding-earth.org</a> <a href="http://www.geocities.com/CapeCanaveral/Launchpad/8098/1.htm" target="_blank">http://www.geocities.com/CapeCanaveral/Launchpad/8098/1.htm</a> <a href="http://www.triplehood.com/peex2.htm" target="_blank">http://www.triplehood.com/peex2.htm</a>

10-02-2002, 12:25 PM	#10
Jesus Tap-Dancin' Christ Veteran Member Join Date: Apr 2001 Location: Heaven Posts: 6,980	Well, a gravity of nearly 40 m/s^2 should be plenty to shut their asses up. Atmospheric pressure would have been huge as well--96 PSI. Would've been damn hard to move, hell, breathe, with that much force bearing down on you. With a radius of nearly half of what it is today, both those conditions would be true due to the inverse square relationship of gravity. Don't these people think about THAT kind of shit? Life would not have existed. Period.

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