CompuServe Messages

Hi, Kamron– >> We discussed how the ridge continues to telescope previous conditions into existing like the shift faults being maintained well after the shifting occurred. I expect to see this stitched into the area where the ridge sections stitched together. You could call into play the highly shifted section between Brazil and Africa, IT may have the history recorded there. I am lost as to what you are talking about here. >> They were together in Pangaea. In the models I am looking at N. America & eurasia separated quite a bit from Gondwana(S. America & Africa) looks like more than a few thousands of miles 135 meg ago. This continued to separate to 5 or 6 thousand miles apart as late as 45 meg ago and only recently they are moving back together. N. America is moving back toward Africa?!? That is not plate tectonics as I know it. If you are talking about Africa and India striking Eurasia, that is not moving "back together", since they were never so close going back to Pangaea. >> If N. America got a 100 million year head start on moving away from europe then how did S. America not only catch up but pass N. America in the distance of spreading race in the Atlantic spreading? Why not? There is no reason to expect all spreading ridges to build seafloor at the same rate; indeed every reference that I have which mentions the matter has them varying all the way from 0 to 16 cm/year in spreading rate. The head start was more like 50-60 million years; the N. Atlantic opened between N.America (still part of Laurasia then) and W. Africa in the mid-Triassic and the S. Atlantic opened between S. America and Africa at the end of the Jurassic. –Doug