3-D Technology Offers Clues to How Egypt’s Pyramids Were Built | Nat Geo Live

My archaeological team actually is very unique because I'm the only ecologist, and the other members are computer scientists, software engineers, and applied mathematicians. We are like a crime scene investigation, patiently documenting with the latest technology the construction technique of a pyramid.

Today, I'm going to talk about one of the most exciting experiences in my academic life, which is climbing the Great Pyramid. I've been fascinated by ancient Egypt since the time of high school, but the reason why I climbed the pyramid is not just out of fascination. The purpose of climbing the pyramid for an ecologist is to obtain data.

The traditional approach to the study of ancient Egypt is like a jigsaw puzzle. We, ecologists, collect the data from the excavation site and then start to describe the past. However, as a consequence, actual survey data is less frequently updated. This is particularly true for the pyramids at Giza, and such traditional documentation is often done by line drawing, which does not represent the actual state of the monument. Such critical documentation only focuses on external parts of the pyramid and spaces such as chambers and corridors. Therefore, no observation of the core of the pyramid has been made.

There are three kinds of hypotheses. Probably, the core of the pyramid may consist of horizontal valence blocks, or some ejectors just deep. Maybe it has a stepped pyramid, or the core may be built by what we call an acceleration layer, but we don't know which is true. The input of the study of the construction will be related to the construction technique, namely the type of ramp the ancient Egyptians employed. For example, if a ramp is straight, maybe this is suitable for setting and arranging the blocks. If a pyramid has a core step, probably in a zigzag ramp, you know the EGD set on the core up or implement has a layer we call an “spinal amber up.”

But we don't know which is correct. Luckily, there is a place where we can actually observe the core structure of the pyramid, which is located 80 meters from the ground, so you have to actually climb up the pyramid. It was quite an experience for me because this is an ancient monument; you have to climb without any safety measures or logs. After two and a half hours, we reached this area, which is an open space called “knotch.” Interestingly, this knot has a kind of crevice in the west, which led to another small open space called “cave.”

We really wanted to document this area; however, we could not actually bring any heavy equipment such as laser scanners because that equipment is heavy and big. But we had to somewhat make archaeological documentation using video footage. My archaeological team truly is very unique because I am the only ecologist, and the other members are computer scientists, software engineers, and applied mathematicians.

The computer scientists came up with the idea to employ a structure from motion technique. So, this technique allows you to stitch images from the video footage for the reconstruction of our study area. We had 20 minutes of video footage, which translated to 300,000 images. This is our result. This is the first decoding of these areas.

Let's compare our data with previous surveys to determine whether this is horizontally arranged blocks, a stepped core, or layers. This is also a photographic section produced from our 3D data. As you can see here, it shows a totally different structure. You may wonder what this is, you know, the cave-like formation. I presume this is a place ancient Egyptians used for packing and the filling of sand and also debris.

This is actually a well-known technique in ancient Egypt called the “chamber method,” which was applied to the construction of temples, cities, and also the pyramids in the Late Period and Middle Kingdom pyramids. This technique accumulates a wall in a remarkably economical way, but we didn’t know this technique actually applied to all the kingdom pyramids. Probably, this is the first one.

So finally, where is the top of the Great Pyramid after climbing and scanning? Again, we used video footage and digital images for the structure from motion process and a multi-booster system. This is the first detailed plan of the top of the pyramid, which can tell us a lot of information. However, by their nature, these images cannot provide pleasant 3D information.

So again, our computer scientists came up with the idea of a new display method of 3D called “picot.” This is a carelessness map, where warmer colors mean shorter distances from the viewer, and cooler colors mean longer distances. The peaks can also indicate ridges, and the valleys, which is also very important for our clerical analysis.

Finally, this is our 3D data. We are like a crime scene investigation; we patiently document with the latest technology and then begin to demonstrate the construction technique of a particular area such as the top of the pyramid and the area on the north end. I hope I can continue to collect the data of important areas around the Pyramid of Giza. Eventually, the reality of the pyramid will be unveiled, which will also tell us the reality of the civilization. Thank you.