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Continents Adrift (Geophysics)
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Oakey Dokey



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How can there be any objections when you have so carefully defined the objects of your own desire? But, having said that, I am quite impressed at having these two categories drawn to our attention. I can't for the life of me see the significance but it does make you look at continents in a whole new way.
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Mick Harper
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In: London
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Next step: add in a time-frame. Let's take an example that orthodoxy is particularly fond of and which has been mentioned here, India. Now orthodoxy is fairly confident that India started out as part of Africa, broke away from Africa, 'drifted' across the Indian Ocean, and finally collided with Asia, thereby pushing up the Himalayas.

OK, all agreed? This happens to be very convenient for us because India illustrates all the possible states-of-a-continent:
1. It is firmly part of Africa ie AfricIndia is one discrete, O-continent
2. AfricIndia starts to split ie Africa and India are now two X-continents
3. India drifts off well into the Indian Ocean ie Africa and India are now two distinct O-continents
4. India starts to collide with Asia ie India and Asia become two X-continents
5. The process is completed with India firmly lodged as part of Asia and we have a single O-continent once again.

Of course this ignores all other complications but suffice it to say that in this particular situation, at any one snapshot in time, we sometimes have two continents and sometimes we have three, and each continent can sometimes be O and can sometimes be X.

Next question: how long does each last. How long can the average continent be expected to be in the O state and how long in the X state?
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Peter Elmy


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That's a pretty tall order! But assuming you mean ballpark figures I'd offer the following for your five-stage example:
1. India and Africa together -- indeterminate (say, 100 million years)
2. India splitting off -- quite a swift process, geologically speaking! (say, 5 million years)
3. Swanning across the Indian Ocean -- medium (say, 30 million years)
4. Colliding with Asia -- again an "event" (say, 5 million years)
5. India and Asia together -- indeterminate (looks permanent enough, say another 100 million years).

I think I am beginning to see where this is headed.
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Mick Harper
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You're a tower of support, Pete. In fact these numbers would be very close to my own guestimates which is not altogther surprising since they wouldn't be a million miles from what orthodoxy might hazard (you can check out various animated time-lines for drifting continents on the web if you want to know the full range of "expert" opinion.) Actually I'd probably downgrade the two 'hundred million year' marks on the grounds that "indeterminate" shouldn't skew the final outcome so much but no matter.

Now this is important: the whole of the remainder of this thread (and the fate of the entirety of Plate Tectonics, the world's second-favourite Prime Mover Theory) rests on Pete's estimates so if you don't agree with them, sing out now. If you don't say anything your agreement will be taken for granted. Anyone who stays silent now but later on says, "Wah! Wah! I didn't accept your estimates in the first place" will receive a home visit from our crack team of Applied Epistemological "librarians".
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Mick Harper
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No answer, came the stern reply. Good. If a trifle sullen. Let us proceed. Using Pete's figures, the argument runs along these lines:
1) Continents are in an O condition for 230 million years (that's 100 mill plus 30 mill plus 100 mill).
2) Continents are in the X position for ten million years (that's five million plus five million).
3) So the ratio between O and X is 23 to 1.
Actually this is not very precise because it ignores on the one hand that during 2) there is also a continent in the O position but on the other hand it also ignores the fact that during 1) both Africa and Asia might be X continents elsewhere at other points of their very extensive littorals. So let's be on the safe side and assume very conservatively that
4) The ratio between a continent in the O position and the X position is 10 to 1.

Everybody happy?
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DPCrisp


In: Bedfordshire
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My brain hurts, he says sullenly. And I wouldn't say happiness is my dominant emotion at this time. But as far as I'm concerned you may poceed.
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Keimpe


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I'm happy! Whoopee!
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Mick Harper
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Excellent. When it comes to low-level mentation, you two are the benchmarks. Now we're going to take off on one of our Intragalactic Applied Epistemological Surveys (it's a little trick of ours for situations when, as is often the case in geophysics, we only have the single test-case to examine). As we flash through the galaxy we're going to stop briefly at the first hundred worlds which manifest the following properties
    a) has active Plate Tectonics on the go
    b) has half-a-dozen continental landmasses
    c) which cover about one third of the world's surface
    in order to take a landsurvey of every one, ending up naturally with Earth so our boffins at AEL HQ can sort out the number of O continents and the number of X continents on each world. And then summarise the results.
Fortunately, since we already know that O continents tend to outnumber X continents at any one time in the ratio of ten-to-one, we won't need to do the actual space flight, we can just model it mathematically. The figures turn out to be
Chart:
All  continents are O none are X >>>>>> 61 worlds
Four continents are O  two are X >>>>>> 38 worlds
Two  continents are O four are X >>>>>>  0 worlds
No   continents are O  all are X >>>>>>  1 world

Notes on these figures.
1. They are highly "estimated" cos I ain't got the maths. (Do write in)
2. There are no odd numbers because X continents come in pairs (yes I know you can theoretically have three or even five conjoined continents but I've ignored this).
3. The peculiarity of the last entry is due to an artefact error which we shall deal with later.
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Brian Ambrose



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Sorry, only just got here! I don't doubt your maths, Mick (well I do, but you know what I mean) but it occurs to me that one thing has been let slip and that is exactly how do you define an X-continent? Take the grand-daddy of them all, the way that South America fits into the armpit of Africa. It's pretty obvious that South America and Africa was once one (an O-continent) then they start splitting (making them X-continents...I hope I've got this right) and then what? At what point do they cease being X-continents because they've drifted apart sufficiently to be considered two O-continents? I assume they are now so far apart that they are O-continents even though we can still clearly see they were once one.
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Mick Harper
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Good point, Bri. It's a matter of judgement, I agree, but even so I don't think it's wildly subjective. Take a look at this typically Terran bit of "continental drift"



Of course, it is a matter of taste but to my mind this is clearly two "splitting" continents. Unless it's a complete coincidence that both Antarctica and South America happen to have filthy great peninsulas pointing at one another, this is cogent evidence that they are "drifting" apart but the "splitting" process is so recent that there is still an extant trail between them.

On this reading Antarctica is an X-continent. Which by definition would make South America an X-continent as well except that in this latter case we need not rely on "extant trails", there is an actual connection with another continent in the form of the Panama Isthmus. (Confusingly, orthodoxy insists this is a case of South America "colliding" with North America but it's all the same for our purposes.) So North America is an X-continent irrespective of the fact that it is joined to Asia across the Bering Straits at various levels of glaciation.

(Eur)Asia is indubitably an X-continent not just because of the Bering Straits but because it has clear links with Africa at Aden, Suez, Sicily and Gibraltar. So that takes care of Africa too. Leaving just Australia to consider. Now Australia is unique in being vastly distant from all other continents and yet...and yet...between Asia and Australia there is a) an Asian peninsula pointing at Australia (Malaya) b) an Australian peninsula pointing at Asia (Queensland) and c) a sequence of the largest islands in the world directly linking both. Again, is this coincidence or is it recent evidence that two rather larger continents were one in the fairly recent geologic past?

I leave it to you...let's call Australia equivocal. That gives us five and a half continents out of six that are X and one that is X/O. Now we've got the figures for earth we can see how they stack up against all the other similar worlds in the rest of the galaxy:

All continents are O none are X>>>>61 worlds
Four continents are O two are X>>>>38 worlds
Two continents are O four are X>>>>0 worlds
No continents are O all are X>>>>>>1 world

Ah! so now we know the identity of that one world in the list that has all or virtually all X-continents. Now most of you will know by heart Rule 37(c) of the Applied Epistemological Handbook:

Any orthodox theory that relies on a hundred-to-one shot is assumed to be complete bollocks.

So, if Plate Tectonics is not available we'll have to set about finding the true Prime Mover of geophysics.
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admin
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Anybody wishing to do just this is invited to join the The Great Prime Mover Treasure Hunt.
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Ray



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Wait a minute.; you're leaving out the bits that aren't continents at all. Iceland, for example.
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Ray



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Sorree! I was looking at the wrong page
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Marduk


In: berkshire
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OK, so the main reasoning behind plate tectonics in the first place were lemurs. I was always suspicious of those lemurs being both in Africa and in India when it took 100 million years for the continents to move to where they are today from once being joined, and lemurs having been evolved for about 6 million years.

Goddamnit, the lemurs lied to me.
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Martin



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There are many strands of evidence that support 'plate tectonic theory'. These are drawn form a wide variety of disciplines.
Nothing that you have said counters directly observed phenomena.
There is direct evidence of 'oceanic' rock being created at the Mid Atlantic Ridge. The Earth's surface is not expanding so crystal rock is being destroyed (evidence of which comes from the salty gases released by Andean volcanoes). There are many other examples.

I would agree that the boundaries between plates are poorly understood in many places. I am not sure if you mentioned it but the Rift Valley in Africa is thought to be the result of the African continent splitting and will one day form a new ocean (the Red Sea is part of this) thus making Africa an O continent? I would also agree that some plates do not seem to fit the pattern.

However I don't think you are really challenging the crux of the theory.
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