Archaeological context The Sphinx is positioned north of the lower end of the causeway of
Khafre that connects his Pyramid- and Valley Temple. It was created by carving it out of the bedrock, cutting blocks from around its body which were used to construct the Sphinx Temple immediately east of the Sphinx and north of the Valley Temple, aligned to it. Evidence suggests that both the Sphinx and its temple were created only after Khafre's Valley Temple and causeway: • The Sphinx Temple was built on the foundation of the preexisting northern enclosure wall of the Valley Temple. This wall was entirely removed apart from a small portion, which was incorporated into the Sphinx Temple. • Unlike the Valley Temple, both the Sphinx enclosure and the Sphinx Temple remained unfinished. The north and east walls of the enclosure are cut back unevenly and insufficiently. The Sphinx Temple lacks in height and work to fit casing blocks was only partially completed. Lehner suggests that a Sphinx cult wasn't established when work ceased prematurely, hence the relative lack of cultural material from the Old Kingdom. Peter Lacovara, an Egyptologist and curator at the
Michael C. Carlos Museum, assigns "some of the erosional features" on the enclosure walls to
quarrying activities rather than weathering.
Causeway The causeway connecting Khafre's Pyramid and Valley Temple is not oriented to the cardinal directions but runs slanted. The southern wall of the Sphinx enclosure respects this orientation.
Sphinx Temple and Khafre Valley Temple Luminescence dating of the two temples gave dates for the middle to late third millennium BC, concurring with the chronological estimates for Khafre and the 4th dynasty and the
radiocarbon dates for the
pyramids of Giza. Some samples indicated New Kingdom intrusions into the temples. As such, the
Dream Stele between the paws of the Sphinx might have been originally a door lintel of Khafre's valley or pyramid temple. Several hieroglyphic inscriptions were found on the walls of the Khafre temples. as well as several
statues of Khafre or fragments thereof. Schoch argues that the casing was applied long after the core structure was built, stating that "granite facing [of the Sphinx and Valley Temple] is covering deeply weathered limestone [that was] slightly cut back and smoothed out [but not enough] to make the wall perfectly smooth". Lehner responded that the limestone wasn't deeply weathered, but that it was cut back irregularly to fit the harder granite facade to it, pointing to the Menkaure Pyramid Temple where the technique can be clearly seen. Other archaeologists who have made similar criticisms include
Kenneth Feder. Feder wrote:
Erosion Pre-Sphinx erosion Schoch argues that the Giza Plateau is "criss crossed with fractures or joints millions of years old" and that "fissures such as those on the Sphinx enclosure wall can only be produced by water, primarily precipitation, and do bear on the age of the Sphinx." Geoscientist Jørn Christiansen agrees that at least some of the erosion took place before the Sphinx was carved. Stating that water most likely seeped through natural fissures in the limestone before the Sphinx had been carved, causing the walls of the Sphinx enclosure to look like they were carved much earlier than they really were. As such, Christiansen determined that there was no geological evidence to suggest the Sphinx was carved earlier than any other monuments on the Giza plateau. Hawass points to the poor quality of much of the Giza limestone as the basis for the significant erosion levels.
Water erosion After an investigation of the enclosure's geology, Schoch concluded that the most prominent weathering pattern was caused by prolonged and extensive rainfall, pointing to the well-developed undulating vertical profile on the enclosure walls. Other geologists, such as Gauri, disagreed and argued for different erosion forces or a combination of such. Schoch contends that because the last period of significant rainfall seemingly ended between the late fourth and early 3rd millennium BC, the Sphinx's construction must date to 5000 BC or earlier, However, new geoarchaeological evidence suggests the occurrence of heavy rainfalls until the end of the
Old Kingdom, circa 2200 BC. A recent study by Rudolph Kuper and
Stefan Kröpelin, of the
University of Cologne suggest the change from a wet to an arid climate in the Sahara happened gradually with climate changes taking place on a north-to-south gradient. According to this study, arid conditions began in the Egyptian Sahara by 5300 BC. These desert conditions gradually extended to the south with Northern Sudan experiencing an arid climate circa 1500 BC. Egyptologist
Mark Lehner believes this climate change may have been responsible for the severe weathering found on the Sphinx and other sites of the 4th Dynasty. After studying sediment samples in the Nile Valley, Judith Bunbury, a geologist at the University of Cambridge, concluded that climate change in the Giza region may have begun early in the
Old Kingdom, with desert sands arriving in force late in the era. Recently, Schoch pushed back his minimum estimate 5000 years further back, to around the end of the last
ice age. also favour the haloclasty process to explain the erosion features, but have theorised that the weathering was driven by moisture deriving from atmospheric precipitation such as dew. Analysis of the Sphinx's bedrock by the
Getty Conservation Institute (1990–1992) concluded that "Continual salt crystallization, which has a destructive effect on the stone, would explain at least some of the deterioration of the Sphinx." Haloclasty is rejected as an explanation for the vertical erosion features by Schoch because it does not explain all the visible evidence, namely that the water erosion features are not evenly distributed, being concentrated in those areas that would have been particularly exposed to running water, whereas the haloclasty process should have operated evenly on all exposed limestone surfaces. Reader replied to this, stating that these structures "were built on an area of high ground and do not lie within any natural catchment. These tombs will not, therefore, have been exposed to any significant run-off." He concludes that "the fact that they are not significantly degraded, as Schoch has pointed out, demonstrates that rainfall itself has not been a significant agent of degradation in Egypt." Rainfall water run-off, however, has been a more significant factor. Reader cites evidence of flood water damage in another location to illustrate this. Lehner responded that these tombs were protected from erosion by sand and debris for most of their history, asking Schoch and West to clarify which mastabas they were referring to exactly. == References ==