THE SPHINX

 Of the four modes of weathering listed above, some rocks may show one mode overlain by another-thus, in particular cases, the various modes of weathering may be somewhat difficult to sort out. On the whole, however, they are clear and distinct from one another at the Giza site.

What is interpreted as precipitation-induced weathering is the oldest predominant weathering mode identified on the Plateau. It is found to any significant degree on only the oldest structures there, such as on the Sphinx body and the walls of the Sphinx enclosure. Of course, it still rains at Giza on occasion, and thus precipitation-induced weathering can be said to exist on all structures on the Plateau to some small degree; here we are talking in generalities and attempting to look at the broad picture. In many places this precipitation-induced weathering mode has superimposed upon it wind-induced weathering. Presumably the major portion of this precipitation-induced weathering occurred prior to the onset of the current and regime exhibited at Giza (i.e., prior to the modern climatic regime of the Sahara Desert).

 

          On the Sakkara Plateau, some ten miles (sixteen kilometers) to the south of Giza, there are fragile mud-brick structures, mastabas, that are indisputably dated to the First and Second dynasties-presumably several hundred years earlier than the standard dating of the Sphinx-that exhibit no evidence of the precipitation-weathering features seen in the Sphinx enclosure. As noted above, well-documented Old Kingdom tombs at Giza, cut from the identical sequence of limestones as the body of the Sphinx, exhibit well-developed wind-weathering features, but lack significant weathering which is precipitation-induced. For these reasons it can be concluded that the well-developed precipitation-weathering features seen on the Great Sphinx and its associated structures predate Old Kingdom times and, in fact, may well predate dynastic times altogether.

         

        The other two modes of weathering noted above appear to be, on the whole, very recent phenomena that have been most active since ancient times. Other researchers have focused attention on such weatherings relative to the Sphinx, particularly the damage currently being done by mobilized salts.[8] These studies are of extreme importance in the attempt to halt the current destruction of the monument; but it must be remembered that such studies of weathering agents currently damaging the Sphinx may not be of relevance in any attempt at determining the genesis of ancient weathering and erosional features which are observable on it, as well.[9]