Originally Posted By: kallog
Originally Posted By: paul
your going to have a really hard time raising the underground temperature to 100 degrees F.

That's because the ground is cooled during the nighttime (near the surface) and during the winter deeper down.

The other part of the story is that rock is a very very good insulator.

Earth formed from a collision
www.preearth.net

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