iceage writes:
The Sahara today consists of some 3,500,000 square miles of sand
Lots of sand in the Sahara, yes, but it may have formed fairly quickly. I'm sure that there are plenty of examples elsewhere that would cause greater problems for young earthers, like your sandstone one.
quote:
One of the most striking climate changes of the past 11,000 years caused the abrupt desertification of the Saharan and Arabia regions midway through that period. The resulting loss of the Sahara to agricultural pursuits may be an important reason that civilizations were founded along the valleys of the Nile, the Tigris, and the Euphrates.
From:
http://www.sciencedaily.com/...ases/1999/07/990712080500.htm