The Age-Old Riddle of the Sphinx

by Robert M. Schoch

While staying at the Mena House beside the Pyramids with her dance study tour in 1991, editor Shareen El Safy came by a provocative preliminary report entitled “How Old is the Great Sphinx of Giza?” written by Robert M. Schoch, Ph.D. The thesis of his paper had monumental implications for scientists and historians: if his estimates that the Sphinx was built some 4,500 to 2,500 years prior to the accepted date (ca. 2500 B.C.) were true, historians would have to reconsider what they know about Egyptian civilization during that time (7000 to 5000 B.C.). At present, the earliest “firm” date in Egyptian history is around 3,500 B.C., when the (probably mythical) warrior king Menes is said to have united the country. Modern scholars believe that Egypt was essentially a rural, regional and neolithic civilization before the establishment of the Old Kingdom. It has long been asserted that before dynastic times, the peoples of Egypt did not have the technology or social organization required to cut out the core body of the Sphinx.

Shareen’s interest in this subject was further stimulated when she saw several television specials featuring the work which Dr. Schoch was doing in collaboration with independent Egyptologist John Anthony West. When recently contacted, Dr. Schoch graciously agreed to bring us up to date on his work in the following article, written especially for Habibi. We are grateful for his generous contribution.

Great Sphinx and Great Pyramid. Photo: Shareen el Safy

The Great Sphinx, carved out of solid rock, standing 66 feet high and 240 feet long, sits on the edge of the Giza Plateau (just west of Cairo, Egypt) east of the three great pyramids. Many connoisseurs consider the Great Sphinx to be the greatest sculpture on Earth — and not only on account of its size. Even in its present weathered state, the proportions and features of the Great Sphinx attest to a high degree of artistic skill. Most Egyptologists currently attribute the carving of the Great Sphinx to the Old Kingdom Fourth Dynasty Pharaoh Khafre (Chephren), approximately 2500 B.C. by various standard chronologies. In addition the so-called Sphinx Temple (sitting directly in front of the Great Sphinx) and Valley Temple (on the Sphinx’s right side) are also attributed to Khafre.

The independent Egyptologist John Anthony West has proposed an interesting hypothesis: that the Great Sphinx of Giza may be older than its traditional attribution. Primarily on the basis of weathering and erosional features seen on the Great Sphinx and its associated temples, as compared to weathering seen on other structures attributed to the Fourth Dynasty, West suggests that the Sphinx may predate the Fourth Dynasty. West further speculates that the Great Sphinx may actually be thousands of years older than the Fourth Dynasty­—even, perhaps, older than ca. 10,000 B.C.

In the Fall of 1989 West presented a short talk on his hypothesis at Boston University and I talked to him privately at length concerning the subject. During these meetings West pointed out to me that the standard attribution of the Great Sphinx to Khafre is based on a chain of circumstantial evidence, such as a statue of Khafre recovered during the nineteenth century from the Valley Temple, an ambiguous (and now effaced) inscription on a New Kingdom stela of ca. 1400 B.C., an alleged similarity between the face of the Great Sphinx and that of Khafre, and the physical proximity of the Great Sphinx to Khafre’s pyramid. After these meetings my preliminary thoughts were that West’s hypothesis certainly sounded interesting, but I could not render any kind of judgment without seeing the site and monuments in person.

Professor Robert M. Schoch and Egyptologist John Anthony West, North Side Great Sphinx, Giza Plateau, Egypt. Photo: Robert M. Schoch.

West subsequently arranged for me to visit the Giza Plateau with him for a week during June of 1990. During that week I was able to roam the Giza Plateau as a tourist and make casual eyeball observations of the rocks and structures, but we did not have official permission to carry out scientific research and we were not permitted access to the Sphinx enclosure or the Sphinx Temple. From my casual observations it did appear that something funny might be going on relative to the weathering of what are presumably structures of identical ages carved out of what appear to be very similar or identical rocks. It appeared that on the body of the Great Sphinx and on the walls of the Sphinx ditch there are weathered or eroded channels up to two feet deep, whereas Fourth Dynasty tombs are relatively unweathered to the point that one can still clearly read the inscriptions carved into their sides. It seemed that West might be on to something, but weathering and erosional rates are a tricky business.

There was more evidence in favor of West’s theory, though. As far as I could determine, the core of the Sphinx Temple (and possibly the core of the Valley Temple) is constructed out of titanic limestone blocks taken directly from the ditch around the Sphinx. Therefore the limestone core of the Sphinx Temple (and also probably the Valley Temple) must be as old as the Great Sphinx itself. The limestone cores of these temples were later faced by the ancient Egyptians with granite ashlars. Based on my observations of the granite ashlars and the underlying limestone blocks, I believe that the limestone core blocks of both the Sphinx Temple and the Valley Temple were exposed to the elements and underwent considerable weathering and erosion before the granite was put into place. I inquired as to when it is believed that the granite ashlars were put into position. The general Egyptological community agrees that the granite facing on the Sphinx and Valley Temples is attributable to Khafre. On site I found an inscription carved into the granite of the Valley Temple which, on stylistic grounds, appears to be an Old Kingdom inscription.

It seems a good assumption that the limestone core blocks would have been freshly cut (that is, unweathered) when initially used to construct the temples. Therefore if the granite facing is covering deeply weathered limestone, the original limestone structures must predate by a considerable degree the granite facing. Obviously, if the limestone cores (originating from the Sphinx ditch) of the temples predate the granite ashlars, and the granite ashlars are attributable to Khafre of the Fourth Dynasty, then the Great Sphinx was built prior to the reign of Khafre. Thus my working hypothesis was that the Great Sphinx and its associated temples predate, perhaps to a considerable degree, the traditional attribution to the reign of Khafre. I was not then in a position, however, to speculate as to how much earlier than the reign of Khafre the Great Sphinx and its accompanying temples may be. Certainly the considerable degree of weathering, apparently predating the Fourth Dynasty granite ashlars, seen on the core limestone blocks of the Sphinx and Valley Temples, plus the apparent deep weathering to the body of the Great Sphinx as compared to Fourth Dynasty tombs, is intriguing.

Robert M. Schoch at College of General Studies, Boston University. Photo: Boston U. Photo Services

Using stylistic arguments, evidence of various repair campaigns carried out by the ancient Egyptians to the body of the Sphinx, and textual evidence, West has further strengthened the case that the Great Sphinx may predate the reign of Khafre.

One argument against the hypothesis of an older Sphinx is that if the Great Sphinx does predate Khafre there should be other older structures accompanying it. If such structures do exist buried beneath the sands they may be locatable using seismic techniques.

In April of 1991 West and I travelled back to Egypt to continue our work. On this trip we were joined by Dr. Thomas L. Dobecki, a seismologist from Houston, Texas, and a number of other interested individuals (including two geologists and an oceanographer—the limestones from which the Great Sphinx is carved were part of an ancient reef millions of years ago). In Cairo we were briefly joined by Professor Mohamed Gaber Barakat and Professor Eglal Refai (a geologist and geophysicist, respectively, with Cairo University). After much diplomatic work, we finally obtained permission for Dr. Dobecki to carry out some low-level seismic work in the vicinity of the Great Sphinx. We were able to gather a quantity of seismic data, and with this data we have been able to establish subsurface geometries of the bedrock and have located several previously unknown features below the surface (discussed below).

During the April 1991 trip I gained access to the Sphinx enclosure and for the first time was able to touch and inspect the Great Sphinx firsthand. These observations confirmed that the Sphinx bears extraordinarily deep weathering features on its body. These weathering features are seen to even better advantage in the ditch or hollow which was carved around the Great Sphinx to free its body; this results from the many repair campaigns which obscure much of the weathering on the actual body of the Sphinx. This dramatic weathering is virtually unique to the Great Sphinx and is not seen on other Old Kingdom structures in the immediate vicinity, even though many of them appear to be cut or built from very similar or identical limestones. Furthermore, the weathering to the Great Sphinx and the walls of the hollow surrounding it shows features typical of water weathering. A likely candidate seems to be precipitation over long periods of time. Weathering of this type would not normally be expected under desert conditions that seem to have predominated on the Giza Plateau since Old Kingdom times.

As a result of the April 1991 trip my thoughts as to the significance of the two-stage construction seen on both the Sphinx and Valley Temples, and their relationship to the Great Sphinx, were reinforced. It appears that these temples were definitely constructed out of blocks removed from the Sphinx hollow, and the Old Kingdom granite postdates the original limestone structures. Again, to reiterate the comments above, all of this evidence points to the conclusion that the Great Sphinx is older than the reign of the Old Kingdom Pharaoh Khafre.

An obvious question is “How old is the Great Sphinx?” Until recently I have had no answer to this question beyond that it predates Khafre. (Interestingly, a group of scientists from Waseda University, Tokyo, using different criteria and totally independently from our work, came to the same conclusion.) However, one can venture some informed speculation as to the age of the Sphinx. If the Great Sphinx was weathered by precipitation, this suggests that it may have been carved prior to the last period of major precipitation in this part of Egypt. Egypt was subjected to erratic floods and what is sometimes referred to as the Nabtian Pluvial (a period of relatively heavy rainfall) from 12,000 or 10,000 to about 5,000 years ago, and it has been suggested that there were sporadic but relatively heavy rains during the fourth millennium (4,000 to 3,000) B.C., and a less arid climate along the Nile as late as the middle of the third millennium B.C. (with relatively wetter conditions and unusually high Nile floods recorded sporadically during historical times). On this basis one might tentatively suggest that the Great Sphinx was built in very early dynastic times or predynastic times (late fourth millennium or earliest third millennium B.C.). However, one must account for the considerable weathering that appears on the walls of the Sphinx hollow, on the body of the Great Sphinx itself, and on the walls of the Valley and Sphinx Temples in the case of the Great Sphinx and its associated temples, weathering that was apparently covered up or repaired during the Old Kingdom (ca. 2600-2400 B. C.). These latter considerations suggest the possibility that the Great Sphinx may be at least several millennia older than its standard attribution.

Analysis of the seismic data collected in April of 1991 contributes further to exploring the age of the Great Sphinx. Seismic lines taken in front of and along the body of the Great Sphinx on either side (East, North, and South of the Sphinx), indicate that below the surface the limestone is weathered up to six to eight feet deep. However, along the back (West side) of the Great Sphinx the identical limestone has only been weathered to a depth of approximately four feet. These results were completely unexpected. It is the same limestone that surrounds the Great Sphinx, and if the entire body of the Great Sphinx was carved out of living rock at one time, it would be expected that the limestone surrounding it should show the same depth of weathering. My interpretation of the data we collected is that initially only the body and front (Eastern portion) of the Great Sphinx was carved free from the rock, thus projecting from the rock outcropping, while what would later become the back or rump (Western end) of the Sphinx originally merged with the natural rock. Once the body and Eastern end of the Sphinx was carved, the limestone floor surrounding it began to weather, but what was to become the limestone floor behind the Western end of the Sphinx was still protected by a thick layer of solid rock.

A reasonable hypothesis is that when Khafre (ca. 2500 B.C.) repaired and refurbished the Great Sphinx, the Sphinx Temple, and the Valley Temple, he had the back (Western end) of the Great Sphinx carved out and freed from the cliff. Thus at this time the limestone floor on the Western end of the Sphinx began to weather. Based on this chain of reasoning, and given that there is 50% to 100% deeper weathering of the limestone floor on the sides and front of the Sphinx as compared to the floor in back of the Sphinx, we can estimate that the initial carving of the Great Sphinx (i.e., the carving of the main portion of the body and the front) may have been carried out ca. 7,000 to 5,000 B.C. This tentative estimate is probably a minimum date; given that weathering rates may proceed non-linearly (the deeper the weathering is, the slower it may progress due to the fact that it is protected by the overlying material), the possibility remains open that the initial carving of the Great Sphinx may be even older than 9,000 years ago.

In addition to the unanticipated differential weathering around the body of the Great Sphinx, our seismic work also revealed several other interesting subsurface features. For example, there is clear evidence of a couple of subsurface cavities or voids under or near the Great Sphinx, and a possible cavity or chamber under the left paw of the Sphinx. The seismic profiles also indicate that the Great Sphinx and Sphinx Temple sit on a steep cliff (now buried in sand), and beyond this cliff are several elusive downdrop structures in the bedrock surface—these features may be either natural or man-made.

I travelled back to Egypt in June of 1991 to check my data and analyses one more time before presenting my Sphinx work at the Annual Meeting of the Geological Society of America in San Diego during October of 1991. Geologists tend to be an honest lot, and if I was guilty of some major misinterpretation of the data I knew that someone there would let me know. Much to my relief no one pointed out any errors in my data or analysis. In fact many were intrigued by my work and suggested that I call on them if they could be of assistance in the future. To my chagrin, however, certain Egyptologists and archaeologists, none of whom were actually at the meeting or saw my data firsthand, heard about my work through the popular press and immediately started deriding my conclusions about an older Sphinx as impossible.

Checking my data one more time, I made another trip to Egypt in March of 1993. Even as I draw fire from some of my Egyptological colleagues, I continue to gather data that supports the contention that the oldest portion of the Great Sphinx dates back to pre-dynastic times. The Sphinx was built in stages. I estimate that the earliest stage (what I refer to as the core body of the Sphinx) dates back to at least 5000 B.C., and possibly earlier. Later (possibly in Khafre’s time, circa 2500 B.C.—when many Egyptologists think the Sphinx was carved from scratch) the rear of the Sphinx was carved out and the head was recarved. No one knows what the original head looked like; the current head is too small for the body (at least when the Great Sphinx is compared to other Egyptian sphinxes or lions), and shows signs of younger cut marks. Furthermore, it has long been suggested that the face of the Sphinx portrays Khafre, but recently this belief has been questioned. Detective Frank Domingo, formerly a senior forensic officer of the New York City Police Department, undertook a detailed analysis of the face of the Sphinx as compared to the known face of Khafre. After thoroughly studying the problem, Domingo concluded that the face of the Great Sphinx is not the same face as seen on statues of Khafre. Most Egyptologists agree that since Khafre’s time the Sphinx has been restored and refurbished many times. These restorations are most visibly manifested in the form of the layers of stone veneer that cover much of the body and paws of the Sphinx.

My research on the age of the Great Sphinx continues. What is the next step? Once I obtain further funds, plus the necessary permissions from the Egyptian government, I plan to continue collecting data; such data will either falsify or further corroborate the hypothesis of an older Sphinx. In particular I hope to gather more subsurface geological and geophysical data and I plan to continue my stratigraphic, weathering, and geomorphologic studies in the Giza Plateau area. If possible, I would like to convince the Egyptian authorities to allow me to collect a few very small samples of rocks from the Giza Plateau that I can analyze in the laboratory. With such samples I could perform certain mineralogical studies (which could shed further light on weathering rates and regimes). More importantly, I would like to pursue (with the help of other geologists who have kindly volunteered their services) isotopic studies of such rocks. There is the possibility that the exposure age of the rock, which could date the initial carving of the Sphinx, could be determined by measuring the concentration of isotopes produced in situ on the surface of the rock by the bombardment of cosmic rays since it was cut. (Cosmic rays are high-energy particles from outer space, such as protons and neutrons, that constantly bombard the atmosphere. As these particles collide and interact with atoms on a rock surface they produce numerous new isotopes of atoms; in some cases the accumulation of these isotopes can be used to date when a rock surface was initially exposed.) Finally, I hope to search Egypt for the remains of other major structures contemporary to a 5000 B.C. (or possibly older) Sphinx. There is no predicting what might be discovered in this ancient land.

For more information on the age of the Sphinx, the interested reader should consult the following articles:

“Scholars debate age of the Great Sphinx,” by R. M. Schoch. The Chronicle of Higher Education, 15 January 1992, p. B5.

“Redating the Great Sphinx of Giza,” by R. M. Schoch. KMT, A Modern Journal of Ancient Egypt, v. 3, no. 2 (Summer 1992), pp. 52-59, 66-70.

“A Modern Riddle of the Sphinx,” by R. M. Schoch. OMNI, v. 14, no. 11 (August 1992), pp. 46-48, 68-69.

“Dating the Sphinx,” by R. M. Schoch. Conde Nast Traveler, v. 28, no. 2 (February 1993), p. 103 [sidebar to a larger article by J. A. West entitled “Civilization Rethought,” Conde Nast Traveler, v. 28, no. 2 (February 1993), pp. 100-105, 168-171, 175-177; note also the editorial on p. 83].

“Reconsidering the Sphinx,” by R. M. Schoch. OMNI, v. 15, no. 6 (April 1993), p. 31.

“Seismic Investigations in the Vicinity of the Great Sphinx of Giza, Egypt,” by T. L. Dobecki and R. M. Schoch. Geoarchaeology, v. 7, no. 6 (1992), pp. 527-544.

“L’Age du Sphinx de Gizeh: Vers Une Revision Dechirante?” by R. M. Schoch. Kadath, Chroniques des Civilisations Disparues, No. 81 (Winter 1993-1994), pp. 13-53.

“On the Geological Evidence for an Older Sphinx,” by R. M. Schoch. KMT, A Modern Journal of Ancient Egypt, v. 5, no. 2 (Summer 1994), pp. 6-7.

“More Sphinx Debate,” by R. M. Schoch. KMT, A Modern Journal of Ancient Egypt, v. 5, no. 3 (Fall 1994), pp. 4-5.

“How Old is the Great Sphinx?,” by R. M. Schoch. American Research Center in Egypt Annual Meeting, program and abstracts (Toronto, 1994), p. 58.

“Sphinx Links,” by R. M. Schoch. Archaeology, vol. 48, no. 1 (January/February 1995), pp. 10-12.

“The Great Sphinx Controversy,” by R. M. Schoch. Fortean Times, No. 79 (February-March 1995), pp. 34-39.

Readers are also invited to write to Dr. Schoch directly at: College of General Studies, Boston University, 871 Commonwealth Avenue, Boston, Massachusetts 02215, U.S.A.

Dr. Schoch is Associate Professor of Science, College of General Studies, Boston University. In addition to working in Egypt, his research has included studies of 80-million-year-old rocks in North Carolina as well as paleontological research in Pakistan and the Canadian High Arctic.

Dr. Schoch received his bachelor of science degree in geology and bachelor of arts degree in anthropology at George Washington University in 1979. He completed his graduate work at Yale University, earning master of science (1981), master of philosophy (1981), and Ph.D. (1983) degrees in geology and geophysics.

Dr. Schoch has lectured widely on paleontology, stratigraphy, and the age of the Great Sphinx. He is the author of numerous papers, reviews, abstracts, and several books (including Systematics, Functional Morphology and Macroevolution of the Extinct Mammalian Order Taeniodonta, Phylogeny Reconstruction in Paleontology, and Stratigraphy: Principles and Methods). In recognition of Schoch’s paleontological contributions, in 1993 the new genus Schochia, an extinct group of fossil mammals, was named in his honor.

Dr. Schoch’s work on the Sphinx has made news around the world, being covered in such papers as The New York Times, The Washington Post, Newsday [New York], The Independent [London], USA Today, The Boston Globe, Los Angeles Times, The Egyptian Gazette, International Herald Tribune, and The Houston Chronicle. Concerning his Sphinx studies, Schoch has been interviewed on radio and television, including a live interview with Scott Simon on NBC’s “Today Show,” August 22, 1992. The NBC documentary special “The Mystery of the Sphinx” (first aired 10 November 1993) and the BBC Timewatch documentary “Age of the Sphinx” (first aired 27 November 1994) focus on the work of Dr. Schoch and his colleague, John Anthony West, concerning the age of the Sphinx. www.robertschoch.com

Article Copyright 1995 by R. M. Schoch. All rights reserved.

Copyright © Habibi Publications 1992-2002, Shareen El Safy, Publisher.

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