Originally Posted By: Bill S.
Today, the continental crust covers only 35% of the globe" imply a belief that there was the same volume of continental crust present at both times? If so, you would need some evidence about the average thickness at both times.

Yes I believe that the volume of continental crust present at both times is about the same.

There is good reason for believing this.

1) the (surface) area of continental crust present during both periods are much the same.
2) since 99% of the continental crust and mantle is solid there is little chance of the continental crust being added to or subtracted from.

Earth formed from a collision
www.preearth.net

Plate-tectonics is wrong
www.preearth.net/plate.html