Don,

I read something in your post which caught my attention regarding polar shifts. The text said "Because the ocean-floor magnetic striping records the flip-flops in the Earth's magnetic field, scientists, knowing the approximate duration of the reversal, can calculate the average rate of plate movement during a given time span. "

This is the first I've heard of ocean-floor magnetic striping being used to identify polar shifts. Do you have any more information on this? I'd like to get a more accurate picture of how frequent the shifts occur, and look at possible parallels to seismic events.

Thanks, Billion