© Colin Reader 17th March 2000 - all rights reserved


With recent access to the Internet (OK, I know, about time!) I’ve being catching up on things related to Giza, particularly as over recent months, I’ve been in correspondence with Chris Ogilvie-Herald and Ian Lawton, authors of what I consider to be an excellent work - "Giza: The Truth"1.

Those of you that have been following developments on the "Giza: The Truth" website, may have read the text of a paper of mine2 that has been posted on the site - a paper that I have been working on for some four years now. I don’t intend to go into the details of my ideas here - please see the website - but, in summary, I believe that the geological evidence from Giza indicates that the excavation of the Sphinx and the associated construction of the Sphinx temple pre-dates the Fourth Dynasty.

I have reached this conclusion on the basis that the most severely degraded limestones exposed at the Sphinx, lie along the western enclosure walls, at the foot of the sloping Giza plateau. In recent internet postings3, John Anthony West has alluded to a depth of some three feet of weathering on the body of the Sphinx, citing a 1979 paper by Dr Mark Lehner. I am not aware of any paper published by Lehner in that year and would welcome a more complete reference. I wonder, however, whether West is confused in this date and meant to refer to a 1980 paper by Lehner (my reference 4). My reason for thinking this is that Lehner’s 1980 paper was referred to early in the debate5, in which it was stated: "in places the walls of the Sphinx enclosure exhibit over a metre (3.3 feet) of erosion". I wonder whether it is these comments that are the source of West’s confusion, comments which confirm my observation that, rather than the body of the Sphinx, it is the walls of the Sphinx enclosure that are the most heavily degraded.

The presence of deep sub-vertical features and the rounded or coved appearance (a term coined by Schoch) of the western enclosure walls suggests that this degradation is primarily the result of rainfall run-off from the surface of the plateau. As damage to other Old Kingdom structures at Giza testifies, however, heavy rain was experienced at Giza after the Fourth Dynasty - the conventional date for the construction of the Sphinx. Degradation by run-off does not, in itself therefore, require any amendment to the conventional age of the Sphinx.

Immediately up-slope of the Sphinx, however, is a large quarry, known to have been used during the construction of Khufu’s pyramid. Over time, this quarry has become partially backfilled with construction debris and windblown sand which, due to its relatively high permeability, will allow rainfall to infiltrate the deep backfill rather than run-off across the plateau surface. Erosion of the Sphinx enclosure by rainfall run-off is, therefore, unlikely to have continued after Khufu’s quarrying began.

In addition to the Sphinx and Sphinx temple, I have argued that ‘Khafre’s’ causeway and the eastern most part of Khafre’s mortuary temple also pre-date Khufu’s development of the site. This conclusion is based on the relationship of these features with the Sphinx and other features - notably Khufu’s quarries. I consider that together, these structures represent an early site of sun worship - with a temple to the rising sun in the east (the Sphinx temple) and the setting sun in the west (part of the Mortuary temple). The layout of this cult centre was determined by the topography of the site, with the principle features built on locally elevated areas of the plateau - perhaps signifying the concept of the ‘Primeval Mound’. I consider, therefore, that it was the topography of the site that controlled the layout of this early cult-centre, rather than any significant solar or stellar alignments.

I have attributed the original construction of this solar-cult complex to the Early Dynastic Period (EDP) on the basis of the use of stone masonry. Inherent in this argument is that the people who carried out this early construction had developed the ability to work masonry on a large scale, having used blocks of limestone quarried from around the Sphinx to construct the Sphinx temple. It is important to draw a clear distinction here, between the use of monolithic stone blocks and the greater level of expertise and planning required to fit numerous blocks together to produce a structure - true masonry. It is only from the later half of the EDP do we have evidence for the use of stone masonry in Egypt. As I will discuss later, to date the construction of the Sphinx and associated temples any earlier than this requires the ‘invention’ of an advanced culture in Egypt (J.A. West’s ‘Lost Civilisation Theory’3) for which, at present, there is no archaeological or other evidence whatsoever.

My research was undertaken in response to a paper published in the early 1990’s by Professor Robert Schoch5. Schoch was, to his credit, the first geologist to present a reasoned argument in support of the observation that the Sphinx had suffered erosion by water. Schoch attributed this degradation to erosion by rainfall and cited the rains experienced in the terminal phase of the "Nabtian Pluvial" as the principal erosive agent. From this interpretation, Schoch suggested a latest date of 5000BC for the construction of the Sphinx.

Schoch’s work has received support from two authors: a British geologist, David Coxill (who published two papers in the Journal "InScription"6&7) and, following the publication of "Giza: the Truth", David Billington. Both Schoch8 and Billington9 have responded to G:TT by posting criticisms (specifically of Chapter 7), on Billington’s website. They have also criticised my work, noting that whilst I support the concept that the Sphinx is older than Egyptologists accept, they can not agree with my Early Dynastic dating. I also note that Schoch has given up several pages of the revised version of his book "Voices of the Rocks"10 to my ideas, although the text of the book and the text on the internet have much in common.

More recently, Professor James Harrell has re-joined the debate11. Harrell was one of the first geologists to respond to Robert Schoch’s initial papers on the age of the Sphinx12 and has always supported the conventional attribution of the Sphinx to Khafre. In this recent paper, Harrell has further criticised the ideas of both Schoch and myself.

It is interesting to find myself in a position whereby both opposing sides of the Sphinx-age debate are able to both find favour and to criticise my ideas. Before responding to the comments of Schoch, Billington and Harrell, I would like to thank them and the numerous other people (particularly Bob Partridge, Ian Lawton, Chris Ogilvie-Herald and David Rohl) who have taken the trouble to read my paper and have taken an interest in my work.

At the time of writing, my paper remains un-published, however, a draft text is currently under review for publication in Archaeometry (Oxford University). Elements of my 1999 paper and of the text that follows in this article have been requested by the Journal of the Ancient Chronology Forum

The first point I’d like to respond to is one raised by Billington9, who asked why my paper was not discussed in the first edition of G:TT? The answer is simply that I only brought my ideas to the attention of Ian and Chris after reading their book. They were not aware of my paper before then.

Before moving on to discuss the more involved arguments of Schoch (supported by Coxill and Billington), I’d like to address Harrell’s work in light of his most recent paper11.

Harrell’s Recent Paper on the Erosion Within the Sphinx Enclosure

In his early 1990’s paper12, Harrell attributed the degradation of the limestones within the Sphinx enclosure to the so-called ‘wet-sand hypothesis’, in which sand accumulating in the Sphinx enclosure, became wetted by two processes:

  • By high Nile inundation

  • By the wetting of sand by rainfall over the plateau.

The problems with the ‘wet-sand hypothesis’, as I perceive them, are discussed in the introduction and accompanying notes of my original paper2. In his recent paper11, Harrell retracts high Nile inundation as one of the mechanisms for wetting the sand in the Sphinx enclosure, but re-confirms his view that the Sphinx is attributable to Khafre and, specifically, that the degradation within the Sphinx enclosure can be fully interpreted in terms of the climatic conditions which have prevailed over the last 4500 years.

Harrell confirms my observations that the intensity of degradation within the Sphinx enclosure is greatest along the western walls (observations that do not appear to have been noted by any other author in the original debate). However, Harrell rejects my hypothesis that, before Khufu’s quarrying, the sloping Giza plateau would have directed surface run-off at the Sphinx enclosure. He also rejects my argument that Khufu’s quarrying brought an end to this run-off and, therefore, an end to erosion within the Sphinx enclosure. Harrell bases these objections on three primary points:

  • Harrell believes that run-off and, therefore, erosion affects the Sphinx today, citing anecdotal evidence obtained during a recent rainstorm at Giza, in which run-off was observed within the Sphinx enclosure;

  • Harrell’s second objection is that he believes falling rains will not run-off across the limestone plateau but would tend to ‘sink’ into (or infiltrate) joints in the limestone and then move along sub-horizontal bedding planes within the strata;

  • In quarried areas, Harrell supports my view that rainfall would infiltrate the sand backfill, but he believes that this infiltrating water would collect on the limestone that forms the base of the quarry and would then run-off down dip towards the Sphinx as sub-surface flow.

Unfortunately for Harrell’s argument there is a major contradiction inherent in these objections. His statement that run-off can be observed today does not sit particularly well with his second point that, as rainfall would infiltrate the exposed limestones, run-off would not be generated at Giza. This contradiction is maintained when later in his March 2000 paper, Harrell returns to run-off as one of the primary methods by which sand within the Sphinx enclosure will have become wet. Harrell presents a line of reasoning which I have maintained throughout, stating:

"Depending on the intensity of the rainfall, the water would have arrived either mainly as overland surface runoff or subsurface flow." (the italics are mine).

Notwithstanding these contradictions, I readily accept that Giza continues to experience significant rainfall, with annual totals (in the order of 0.5m) recorded in Cairo today. With respect to his first point, following an editorial qualification posted by Ian Lawton on the G:TT website, it now appears that the anecdotal evidence cited by Harrell actually refers to run-off from the south western corner of the Sphinx enclosure only and may be associated with Khafre’s causeway.

With respect to Harrell’s second and third points, I have two fundamental objections to this line of argument. My first objection is that, if rainfall infiltrates the surface limestones why would it not infiltrate the limestones that form the base of the quarry? Secondly, as discussed by Lehner in his seminal paper The Development of the Giza Necropolis: The Khufu Project13, the base of Khufu’s quarries reach up to 30m deep (approx 10m above sea level), lower than the base of the Sphinx enclosure (approx 20m asl). Any sub-surface flow from the base of the quarries is likely, therefore, to pass beneath the Sphinx enclosure, rather than emerge as a series of springs in the face of the western enclosure wall, as Harrell suggests.

Notwithstanding this, it is my opinion that the degradation of the Sphinx enclosure is not consistent with what would be expected from the mechanism described by Harrell. If sub-surface flow emerged as spring lines in the western face of the Sphinx enclosure, a series of open, solution cavities (Karstic features seen elsewhere at Giza) would be evident emerging from deep into the limestone. These features, if present at all, do not dominate the western Sphinx enclosure walls. In fact the most significant degradation consists of the deep sub-vertical features and rounded or coved appearance to the rocks, features that are so typical of surface erosion by flowing water.

Having ‘disposed’ of my argument, Harrell then goes on to describe the work of Gauri et al14, fellow advocates of the conventional Fourth Dynasty age of the Sphinx. Gauri attributes the degradation of the Sphinx to chemical weathering and exfoliation, a process that Harrell views as complimentary to his own ‘wet-sand’ hypothesis. Whilst I accept that Gauri’s chemical weathering has affected the exposed limestones within the Sphinx enclosure, in my July 1999 paper2, I discussed at length the limitations of this process, indicating that it fails to explain the more intense degradation of the western Sphinx enclosure walls.

Both chemical weathering and wet sand are considered by their respective authors to have been particularly active up to the present day and are the cause, they believe, of the more intense degradation in the western Sphinx enclosure. On this basis they argue that it is not necessary for the Sphinx to have been built before the Fourth Dynasty. The evidence from the site, however, is that the processes that led to the more intense degradation of the Sphinx enclosure, are not currently active and have not been experienced for at least the past 2500 years.

This evidence comes from a number of 26th Dynasty tombs (ca 600BC) located close to, and in a similar hydrogeological setting to, the Sphinx. The first of these tombs is the so-called ‘Campbell’s tomb’ a square-sectioned shaft tomb located a short distance to the west (up slope) of the Sphinx enclosure, between the Sphinx and the backfilled Khufu quarry. Like the Sphinx enclosure, Campbell’s tomb was filled with sand, only being cleared in the 1830s. If rain from the quarried plateau was responsible for the continuing wetting of accumulated sand and for the degradation of the Sphinx enclosure, as Harrell argues, features of erosion similar to those in the west of the Sphinx enclosure would be expected on the western walls of Campbell’s tomb. Such features are not, however, present. Some may argue that the difference in degradation is simply due to the Sphinx being the older of the two monuments, however, it is not the intensity, but the nature of the degradation that is so markedly different, with the exposed limestone in Campbell’s tomb showing not even the slightest evidence of the coved appearance that characterises the western Sphinx enclosure walls.

There is, however, even stronger evidence that the processes that led to the degradation of the western Sphinx enclosure are not active today and have not been active since the 26th Dynasty. Three 26th Dynasty tombs have been cut into the limestone beds exposed along the western enclosure wall. Although the strata into which these tombs were cut are intensely degraded, the tomb portals still show extensive chisel marks made during their excavation, evidence that recent degradation has not be particularly aggressive. These portals are exposed to direct sunlight for much of the day and, as with the Sphinx, they were buried in sand for long periods of time. If chemical weathering or Harrell’s wet sand hypothesis had been significant agents of degradation, it is without doubt that the portals of these tombs would have been affected. It is quite clear, therefore, that the intense degradation of the Sphinx enclosure walls can not be attributed to any degradational processes that have been active since 600BC.

It is possible to extend this argument even further back in time. According to the well-respected and widely accepted reconstruction of the climate, established by Karl Butzer15, the weather conditions experienced today at Giza have not changed significantly since ca. 2350BC (towards the end of the Fifth Dynasty). If the rounded features of degradation that characterise the western Sphinx enclosure have not developed since the 26th Dynasty, there is no reason to believe that they would have developed during the period between the 26th Dynasty and the end of the Fifth Dynasty, particularly, as Butzer has stated, the climatic conditions have changed very little during this time.

The evidence from the 26th Dynasty tombs suggests, therefore, that neither chemical weathering, wet sand or rainfall have been responsible for the intense degradation of the limestone exposed in the western Sphinx enclosure and that the erosion present must have developed under a different degradational regime. I consider that the most significant change to the degradational regime at Giza came with the excavation of Khufu’s quarries, which brought an end to the possibility that rainfall run-off could discharge into the western Sphinx enclosure.

Finally, Harrell also objects to my pre-Fourth Dynasty attribution for the alignment of ‘Khafre’s’ causeway. I based this conclusion on the fact that this linear body of rock had survived Khufu’s quarrying of the site, which suggests that it was a feature of some importance (consistent with my view that it was part of an early site of solar-worship). Harrell considers that when Khufu was developing the site, his son’s mortuary complex (i.e. Khafre) may well have already been in the planning stage and the alignment of the causeway may have already been established. This argument, however, neglects any consideration of the reign of Djedefre, Khufu’s direct successor, who began the construction of his mortuary complex at Abu Rawash. I consider that the shift in location to Abu Rawash severely weakens any consideration of a ‘masterplan’ for the Giza site.

Schoch’s Dating of the Sphinx

Schoch dates the excavation of the Sphinx to a period before 5000BC and supports this date by three principal lines of argument:

  • The limestones within the Sphinx enclosure show clear signs of erosion by water which, under Schoch’s interpretation, is the result of rainfall during the terminal phases of the "Nabtian Pluvial" - a period which lasted until 5000BC;

  • Schoch’s interpretation of geophysical survey within the Sphinx enclosure, suggests that the depth of weathered limestones immediately to the west of the Sphinx (that is behind the rump) is significantly less than the depth of weathering elsewhere, indicating a two phase construction of the Sphinx enclosure. Dating the shallower weathering to the Fourth Dynasty, Schoch argues an earlier date (before 5000BC) for the excavation of the more deeply weathered parts of the floor of the Sphinx enclosure;

  • First Dynasty mastabas at Saqqara, built in mudbrick, show no evidence of erosion by rain and, according to Schoch, must therefore have been built later than the Sphinx.

Although this argument appears persuasive, there are a number of inherent weaknesses and one fundamental flaw: that a pre-5000BC date for the Sphinx does not fit into any known context.

A Context for the Sphinx

In G:TT, Ian Lawton and Chris Ogilvie-Herald have a chapter titled Context is King. For a site such as Giza, in which there is strong evidence for Fourth Dynasty activity, context is widely used to date an artefact. It is the strength of the context from Giza that has supported the attribution of the Sphinx to Khafre for so long and it is only when hitherto unknown and detailed evidence comes to light, such as the geological evidence described by Schoch and, subsequently, myself does the context begin to weaken.

Having advocated a pre 5000BC date for the excavation of the Sphinx, Schoch has attempted to establish a role or context for his early Sphinx. In search of such a context, Schoch has suggested links with Jericho (from where stone masonry is known, ca. 8000BC) and to stone artefacts from the Nabta Playa in southern Egypt from about 6000BC.

I have investigated these suggested links and have found them both unconvincing. With respect to the possibility of links with Jericho, Michael Baigent in his book Ancient Traces16 links Predynastic pots found at Giza (see also my paper2), to evidence of traders from the Jericho region who had settled in the Late Predynastic town of Maadi, across the Nile valley from Giza. Baigent describes how many of the pottery remains encountered during the archaeological excavation at Maadi, were clearly influenced by Jericho - evidence, he concluded, that people from Jericho had settled in Maadi, bringing with them their knowledge of working masonry and, he implies, building the Sphinx.

Whilst this link is intriguing, it can not be substantiated by archaeological evidence from the site. An important publication on the subject is "Maadi I - the pottery of the PreDynastic Settlement"17, in which the authors discuss the presence of Palestinian (including Jericho) pots of Chalcolithic age (4000-3000BC). Not only is this date not consistent with the 5000BC date advocated by Schoch for the construction of the Sphinx, the authors note that the Palestinian pots were of a single type and represented only some 3% of the total assemblage. Given the rich variety of forms of Palestinian ware, the firm conclusion reached was that these pots were not imported in their own right, nor were they brought with settlers - their presence in Egypt was simply due to the fact that they were the standard container for a certain class of goods imported from Palestine.

As for the Nabta Playa, well the Sphinx and Sphinx temple actually have very little in common with the stone circle discovered at this site in southern Egypt (dated to approximately 6000BC18). The scale of the two monuments could not be different, the Sphinx is some 74m long, whereas the Nabta circle is only 4m in diameter. Unlike the Sphinx temple particularly, which consists of carefully quarried, worked and placed masonry, the Nabta circle is built from roughly hewn blocks. A number of large worked stones have also been found buried in the sand at Nabta. Whilst these monoliths show some advanced features of working in stone, they do not represent masonry and can not, therefore, be associated with the Sphinx.

These distant sites (Jericho and Nabta) fail to provide the early context for the Sphinx that Schoch has sought. More to the point, however, is that we do have archaeological evidence from Egypt for the period ca. 5000BC. The capabilities of the culture from this time are well established, however, they do not include the working of stone masonry.

Schoch’s Geophysical Investigations

On the recent Internet posting8, criticising Chapter 7 of G:TT, and in his recent book "Voices of the Rocks", Schoch has made the point that I have not commented on the geophysical data that he had obtained from within the Sphinx enclosure, nor have I considered the implications of this work on the dating of the Sphinx.

My reason for not addressing the seismic investigations was primarily connected with the value of this form of investigation when used in isolation. Geophysics, provides an immensely useful range of non-destructive tools, however, in all cases these techniques can merely be considered as prospecting tools. It is common for one geophysical technique to show anomalies where no features exist and visa versa. In addition, different results can often be obtained by the same technique if additional factors come into play. Conclusions drawn from geophysical investigation should always be confirmed by intrusive methods. No intrusive investigation has been undertaken by Schoch.

An illustration of the vagaries of geophysical survey is provided by the team from Waseda University in Japan (Yoshimura et al19&20), who used two advanced geophysical techniques within the Sphinx enclosure: ground penetrating radar (GPR) and microgravity techniques. In their first season, Yoshimura et al used GPR with a frequency of 150MHz and identified two potential cavities in front of the Sphinx. During their second season, however, the same techniques were used but with a reduced frequency of 80MHz: no significant anomalies were encountered at the appropriate locations. It is not possible to be certain which set of geophysical data is to be believed, however, as Yoshimura et al state20 - ‘It was found that the existence of a cavity could not be confirmed without a boring operation’.

In Schoch’s opinion, however, the seismic geophysical surveys undertaken by Dr Thomas Dobecki and himself21 confirm his pre-5000BC date for the original construction of the Sphinx. Schoch’s argument can be summarised as follows:

After excavation of the Sphinx, the newly exposed rocks, particularly the floor of the enclosure, began to weather. In his recent criticism of G:TT8, Schoch appears to advocate arid, sub-aerial weathering as the main agent of this degradation, dismissing the effect of modern rainfall etc. However, in his earlier papers, particularly the first paper that he co-wrote with Dobecki21, a wider range of weathering agents are considered including sub-surface dissolution and karstic development (related to dissolution of the limestone). Schoch considered that if the Sphinx had been carved in one operation, the depth of weathering below the floor of the Sphinx enclosure would be uniform. He argued that the shallower weathering at the rear of the Sphinx, indicated that the excavation at this location had been cut more recently. Zahi Hawass22 has indicated that a number of masonry blocks on the rear of the Sphinx, date from the Fourth Dynasty. Schoch associated this restoration with excavation at the rear of the Sphinx and, on this basis, argued that the more shallow weathering represented a late phase of excavation, limited to the rear of the Sphinx enclosure, which had been undertaken in the Fourth Dynasty. As the weathering elsewhere across the floor of the enclosure is between ‘fifty to 100%’ deeper, Schoch argued that the enclosure had been excavated some 50 to 100% earlier than the Fourth Dynasty - that is about 7000 to 5000BC. In this way, Schoch‘s was able to ‘confirm’ his early date for the Sphinx, which he had initially established on the basis of a known period of rainfall.

It is necessary to question, however, the validity of Schoch’s key assumption: that the results of the seismic geophysics actually represent evidence for weathering rather than some other factor. Schoch’s conclusion, that the seismic survey indicates anomalous shallow weathering at the rear of the Sphinx, is only one possible interpretation of the data. As discussed by Harrell11, there are other equally valid interpretations, including one in particular that may cast some doubt on Schoch’s interpretation.

In his original KMT article5 Schoch discusses four seismic lines within the Sphinx enclosure. The line at the rear of the Sphinx (line S3) suggested a depth of weathered limestone in the order of 1.2m. Three further lines (S1, S2 and S4) on the north and south of the Sphinx, parallel to the body and in front of the paws, indicated weathered rock to 1.8 to 2.5m depth. However, the KMT article simplified the original seismic work, omitting any discussion of seismic line S9, which ran across the floor of the Sphinx temple. In their joint paper21, Dobecki and Schoch report that S9 indicated weathering to 1.2-1.5m depth. In addition, they state that the depth of weathering indicated by S4 (in front of the Sphinx) approached 4m, not the 2.5m stated by Schoch in KMT. If these depths are plotted on an east-west section through the Sphinx enclosure and Sphinx temple (bearing in mind that the floor of the Sphinx temple is cut three metres lower than the floor of the Sphinx enclosure) the ‘weathered’ depths can be connected by a sub-horizontal line that closely parallels the dip of the strata. Schoch’s ‘weathered zone’ may, therefore, be a function of the structure of the Member I rock - reflecting the bedding of the limestones beneath the Sphinx enclosure.

The ‘Unweathered’ First and Second Dynasty Mastabas at Saqqara

A series of First and Second Dynasty mudbrick tombs are situated on a limestone ridge at Saqqara, overlooking the Nile Valley. These early tombs, which conventionally are considered to pre-date the Sphinx, show little evidence of degradation by rainfall. Schoch has taken this in support of his pre-5000BC date for the Sphinx, arguing that the rainfall which eroded the early Sphinx had ended by the time the later mudbrick tombs were built.

We know, however, that significant rainfall has been experienced in Egypt and that, in the appropriate hydrological setting, the resultant run-off can lead to considerable destruction. Reisner showed that sometime after its Fourth Dynasty construction, mudbrick elements of Menkaure’s valley temple were damaged by rainfall run-off. I also consider run-off to be a significant agent of degradation at the Sphinx. Unlike the Sphinx and Menkaure’s valley temple, however, the mudbrick tombs at Saqqara 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.

That the First and Second Dynasty mudbrick tombs at Saqqara do not show any evidence for erosion is, therefore, a function of their hydrological setting rather than their age. Although it is beyond question that these tombs will have been exposed to rainfall, 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.

The Sphinx Temple and Khafre Valley Temple

Schoch has also suggested that the Sphinx temple and Khafre’s valley temple are also older than generally thought, having reached this conclusion on the basis of the condition of the masonry of the temples. In support of this idea they cited work by Dr. Mark Lehner4. Lehner argued that the masonry used to build the Sphinx and Khafre valley temples was quarried from within the Sphinx enclosure. The concept of the Sphinx as a source of building stone for both temples appears, however, to be the result of some confusion.

On p127 of the Complete Pyramids23, Lehner uses the word ‘probably’ when discussing the Sphinx enclosure as the source of the masonry for Khafre’s valley temple. In an article in Archaeology24, Lehner is even more circumspect (p33) "..Khafre Valley Temple [was built] from huge blocks of limestone…..that were quarried from the upper layers of rock corresponding to those of the Sphinx head and possibly higher". I also draw your attention to the figure at the top of p207 of the Complete Pyramids. The caption quite clearly states that "Monoliths for Khafre’s temples were channelled out of a quarry southwest of the Sphinx".

If there is a lack of clarity on this issue, it is possibly because of a working hypothesis Lehner developed during the original ARCE Sphinx Project. Lehner postulated that Khafre’s valley temple had been constructed from the Member I rock quarried to form the platform for the Sphinx temple and then the Sphinx temple had been built from Member II rocks quarried from round the Sphinx.

When Lehner tasked a geologist with confirming this, that geologist - Thomas Aigner - was unable to do so. "A typology of core blocks was established on the basis of lithological and paleontological features. The attempt was then made to trace the individual and/or broad types of blocks to the geological stratification and to the horizontal distribution of the facies within given units. In general the study confirmed an earlier hypothesis that the core blocks of the Sphinx Temple derive from the quarry immediately to the west from which the Sphinx was formed. The earlier suggestion that the blocks of the Khafre Valley Temple were taken from the cut into the Member I which created the lower terrace of the Sphinx complex was definitely nullified by Aigner’s study."25

So, whilst it has been proven that the masonry used for the construction of the Sphinx temple was quarried from within the Sphinx enclosure (indicating that the Sphinx and associated temple are of the same age) the source of masonry for the valley temple is by no means proven. It can not be stated, therefore, that Khafre’s valley temple is contemporaneous with the Sphinx.

Schoch and Billingtons’ View of My Dating of the Sphinx

As discussed above, I attribute the construction of the Sphinx and associated structures to a time when, on the basis of archaeological evidence, the inhabitants of Ancient Egypt had established the skills of working stone masonry - tentatively, the second half of the Early Dynastic Period. This limits the period of time available for the development of the more intense degradation of the Sphinx enclosure to a few centuries rather than the millennia available under Schoch’s dating. Neither, Schoch nor Billington (who by his own admission, is not a geologist) consider that my dating allows sufficient time.

In the preceding sections of this paper, a number of issues have been explored and conclusions drawn. It is probably worth reviewing these issues with respect to the age of the Sphinx:

  • The climatic record for Egypt indicates that, although conditions have been predominantly arid, it has rained. Modern rainfall statistics show that, although significant annual rainfall totals have been recorded, most of the rain falls in relatively short periods. Such short rainy seasons, together with suitable ground conditions (such as those provided by the fine grained limestones at Giza) lend themselves to the generation of run-off. These conditions have extended back until the late Fifth Dynasty, before which the climate was notably wetter. The general absence of erosion features on the Early Dynastic mastabas at Saqqara and the 26th Dynasty tombs at Giza suggests that the actual rainfall that has been experienced is not responsible for intense degradation.

  • We know from Reisner’s work at Menkaure’s valley temple, that run-off has occurred at Giza and has the potential to cause erosion and structural damage. Menkaure’s valley temple is located in a wadi feature and the damage that it suffered (after the Fourth Dynasty) was largely due to the hydrological setting of the temple. Given the hydrological setting of the Sphinx, erosion by rainfall run-off should be expected. Not only is the Sphinx situated at the foot of the sloping Giza plateau, it is also within the catchment of a wadi (the lesser wadi, identified in my 1999 paper2). The low knoll of limestone, from which the Sphinx was carved, formed the southern bank of this wadi and as the floor of the Sphinx enclosure is probably lower than the wadi floor, the excavation of the Sphinx is likely to have directed run-off into the Sphinx enclosure.

  • In my original paper I argued that the quarrying of the site undertaken during the reign of Khufu will have prevented run-off reaching the Sphinx because, rain falling on the quarry would infiltrate the relatively permeable accumulated sand rather than run-off across the surface. Given that it does rain at Giza and that none of the 26th Dynasty tombs, in the same hydrological setting as the Sphinx, show any of the features of erosion present along the western enclosure walls, the evidence from the site confirms this view. The intense degradation of the Sphinx enclosure, therefore, can only be the result of run-off that occurred before Khufu’s quarrying began.

  • In searching for a context for an early Sphinx, I have sought a period in Ancient Egyptian history in which use of stone masonry is known from the archaeological record - that is the Early Dynastic Period. As discussed in my paper2, but seldom discussed elsewhere, late pre-Dynastic and Early Dynastic finds have been discovered at Giza during archaeological investigation and reported in reputable journals. Furthermore, the development and probable role of the early Sphinx and its associated eastern and western temples, can be seen to parallel the development in sun-worship in Egypt. I have not deliberately sought to uphold the Dynastic (or any) age of the Sphinx, however, the excavation of the Sphinx must be set in a demonstrable context. The archaeological record clearly does not support the 5000BC date for the Sphinx, let alone West’s ‘Lost Civilisation’ hypothesis.

Can run-off discharging into the western Sphinx enclosure during the latter half of the Early Dynastic Period account for the degradation that is present? I touched on this matter in the 1999 revision of my paper2 and argue that, on a face exposed to Gauri’s processes of chemical weathering and exfoliation, soluble salts will first be drawn towards the surface of the rock and will then be exposed to leaching and abrasion once exfoliation has occurred. As weathering progresses, soluble salts are removed from increasing depth, leaving an increasingly insoluble matrix near the surface. This process can, therefore, be seen to be somewhat self-limiting and it is only when a chemically weathered face is subject to erosion - such as from rainfall runoff - will the insoluble veneer be abraded off, exposing salt-rich rocks from the sub-surface. These newly exposed rocks will, once again, begin to rapidly weather and so the cycle repeats.

If, as I maintain, the Sphinx was excavated in the second half of the Early Dynastic Period, it will have been subjected to the cyclical degradation described above - with fairly arid conditions experienced for much of the year and more intense seasonally distributed rains leading to run-off into the western Sphinx enclosure. Under this scenario, the western Sphinx exposures will have gone through a large number of weathering/erosion cycles in the few centuries allowed by my dating, constantly regenerating the degradation of the western exposures and leading to the comparatively rapid degradation of the exposed limestone. There does exist, therefore, a clear mechanism by which the pattern and nature of the degradation within the Sphinx enclosure can be interpreted in terms of an Early Dynastic date rather than the much earlier date advocated by Schoch.


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2.       Reader, C.D., October 1997, revised August 1999, Khufu Knew the Sphinx.

3.       West, J.A., March 2000,Giza:The (Half) Truth V - In Defense of the Personal Attack, posted on the Internet site "The Daily Grail".

4.       Lehner, M. et al, 1980, The ARCE Sphinx Project - A Preliminary Report. NARCE, 112, p 3-33.

5.       Schoch, R.M., 1992, Redating the Great Sphinx of Giza, KMT Vol 3 No. 2, p53-59 & p66-70.

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7.       Coxill, D, 1999. How Old did the Ancient Egyptians Regard the Sphinx, InScription - Journal of Ancient Egypt.

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