In this instance ( in contrast to conventional plate-tectonic reconstuctions, made on a constant radius of the Earth's present 12,800 km diameter) these shields re-assemble into a smooth featureless sphere approximately 4,800 km in diameter ( or a diameter similar to that of Mercury. see: Mercury ). Their magnetic striping realigns into parallel lines running equatorially ( in relation to the present position of the equator ).

But, more interestingly, there is a huge hole in the side of it, 2,000 km wide, between the Indian and African shields, exactly where the Himalayas are now.

Areas of present volcanic and earthquake activity realign and emanate from this hole, running around the sphere, along the North African and South American shield boundaries, meeting on the other side, at the antipode of the hole, at the point which will become the San Andreas Fault.

( The surface magnetic field used in this reconstruction is based on the World Magnetic Declination Field from 1995. Magnetic declination varies locally from year to year but is connected to the overall crustal or surface magnetic field which remains consistent. Click here for: World Declination Map )