National Geographic "Book" on Deserts

[rhinodynamo]

I know this is going to sound a little obsessive, but I remember seeing on an old Yahoo group ,a pic of a guy in thick deep-looking mud. When I asked the poster where he got it, he said it was from an old National Geographic "book" on deserts. The picture looked pretty current, like maybe from the 90's and I was never sure if by "book" he meant magazine. Does anyone know the book or magazine he was referring to?