CompuServe Messages

#Subduction & Ocean Basin

    22-Feb-95 23:19:51
Fm: Doug Mitchell 70621,702
To: Kamron Kirkconnell 73740,2246
Hi, Kamron– >> Still the planes run in all directions so it still is tough to see it sliding smoothly in any direction. Planes in many directions just mean there are more options for sliding in more directions. Actually, I have been talking "bonds" when we are mainly dealing with ionic substances. Imagine two boards, studded with magnets at constant intervals (all the magnets in one board are pointed the same way). Put the boards parallel together turned so the magnets on one board attract those in the other board, and bring the boards close. They will snap together, with each magnet touching its counterpart in the other board. Now push along the length of one board. It resists. Push harder – the boards may slip one magnet-separation-distance so the magnets are paired again, but each with a new "partner" on the other board. Make them into planar boards with magnets in a regular two dimensional array, and you see what happens at a cleavage plane in a solid – notice there are now two directions where you can push the boards so the magnets all switch partners at once. Array this in three dimensions (now you need "boards" that can pass through each other), and you have solid flow. Pushing the boards really hard so the attraction is totally overcome and they fly apart would be like breaking the solid. Pulling the magnets out of the boards and jumbling them together in a pliable mass would be the equivalent of liquefying the solid. >> It is obvious that the ocean basin faults in true lines straight and slight to moderate large curves. Some of the faults are thousands of miles long. So we know that it breaks like a brittle solid. All this proves is that it breaks like a brittle solid under _some_ conditions – sharper stress in shorter time, and there is no time for bonds to be rearranged. Hit old silly putty sharply with a hammer and it breaks – does that mean it cannot be shaped without cracking? >> The smooth continuous Atlantic ocean basin ridge shows no signs that N. America split apart 35 million years before S. America. Why the ^#$$%! should the _ridge_ show any such signs? It is brand new at every point, exactly as plate tectonics says it must be. If you meant seafloor, well aside from paleomagnetic, radioisotope, and fossil dating, I cannot think of much evidence of the earlier separation of N.America from Pangaea. I suspect there are ocean fossils from the N. American eastern seaboard and/or the W. African facing coast that pre-date the Cretaceous/Tertiary boundary, which would be a toughie for your theory but predictable from plate tectonics. >> And where did the ocean basin between N&S americas go? If they did move together, it went into the mantle, of course. I think they moved more apart than together – in Pangaea, S. America (Colombia) was up against what is now the _west_ coast of Mexico and C. America, which were folded up so there was no Caribbean separating them from N.America. Room had to open up between them for C. America to straighten up in; I believe it arose because N. America headed somewhat northwest while S. America went a little more west or southwest. I cannot imagine fitting the continents together without that folding of C. America; at the very least you would have to disregard the common formations connecting the continents where standard theory puts them, which is the chief evidence they ever were connected. >> Why would they fit together so well if they have been deformed over and over? They have not been deformed much since the breakup of Pangaea (when the spreading zones sliced them apart into brand new shapes with little regard for any _past_ deformations). –Doug