As I said earlier, I'm not following this issue in detail, but certain things do catch my attention. In the last post I was curious about the following passage:
" If there was widespread agreement that the Deccan Traps were antipodal, why didn't we see India shown far to the east of its supposed location off Africa 65 MYA, according to the Standard Theory? I've never seen anything showing India India anywhere near where I locate it 65 MYA (at the antipode). Everything I have seen shows India located off of Africa 65 MYA, moving over the Reunion hotspot to create the Deccan Traps and then moving to its present location."
So is there an argument about where India was located relative to the other continents at the time? I am under the inpression that the positions of the landmasses in the past have been determined by studies of remnant paleomagnetism in igneous rocks and it has proven quite useful and fairly accurate for that purpose. One of my geophysics courses included a section on this subject and it was quite enlightening to learn that as igneous rocks solidify the magnetic grains (esp. magnetite) align themselves with earth's magneitic field so we can now determine the latitude and direction toward the magnetic poles in the ancient rocks. It is easy enough to see these values change moving up in the geologic succession as the contiments moved. Longitude is something of a problem but seens to have been worked out by other means.
The subject of paleomagnetism doesn't get much attention, which leaves a lot of room for bizarre speculations about continents catestrophically sliding over the earth to new new climatic zones (as in the claim that mammoths frozen with cuds of grass in their mouths show a sudden slipping of continents).
Just wondering.
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