But, more significantly,
I found that, especially when overlaid on a map of the Pre-Cambrian
Shields ( the earliest areas of rock on the planet's surface, which
lie in the centres of the continents - and taking into account my
premise of closing the Pacific ) the magnetic striping of Africa
and India then suggested that these oldest areas of rock
could be regarded separately as a single
shattered shield, even smaller than the re-assembly which closed
at the continental shelves, which I had already made.
This is why I then re-assembled only these
original Pre-Cambrian Shields independently of the present sphere.