Jammer,

Giza is known to have a torrential rain shower every year or so. If the sphinx were normal rock, it wouldn't affect it much.

However, the sphinx is not normal rock. It is made of limestone with a high salt content. This salt fills with water from dew every morning, then quickly evaporates on the north and west walls as the sun rises. This rapid evaporation causes the salt crystals to contract quickly and thus destabilizes the chemical bonds of the limestone.

Once this happens, the layers of limestone on top will peel off, like scales. This scaling is called "salt exfoliation", and Lauri has done an enormous amount of research into it. The scaling, however, is not enough to account for the wear we see today. But, when you combine it with the occasional torrential rain, you end up with the exact geologic profile we see on the sphinx and the enclosure today.

Of course, you can also add some of Harrel's wet sand to the process (the wet sand filling the enclosure whenever it wasn't being properly maintained would also erode the limestone) and as you've mentioned, wind erosion. It's really a wonder that after 4500 years there's anything left of the poor beastie.

Schoch's work is absurdly simplistic in order to push his date back as far as possible. He uses one element, rainfall, while ignoring the obvious effects of the other factors we clearly see evidenced at Giza today.

Anthony

You can lead a horse to water but you can't make him think.