[autokad]

also whats interesting is that 66 million years ago, the continents were mostly where they are now. 120 million years ago Africa was touching Brazil

[ggm]

ie the rate of movement is not a constant, speed of continental drift varies over time?

[autokad]

yeah, they expand faster at first and slow down afterwards until something else happens.

I was looking at the ocean floor and using smooth ocean floor as 'fast moving' and rough ocean floor as 'slow moving'.

South America is moving 3 cm / year. using that with the ocean floors and some guestimation,,, between 120 and 113 m years ago SA moved about 12 cm / year and slowed down to 3 betwen 113 m years ago and now. Assuming no movement from Africa