Why Earthquakes Haven’t Wrecked Egypt’s Great Pyramid

Civilizations may fall. But Egypt’s Great Pyramid of Giza has stood for nearly 5,000 years. Scientists finally know how it survived earthquakes.

The pyramid tends to vibrate differently than the soil around it. This prevents excessive shaking during an earthquake. The pyramid also has a sturdy shape and structures within it that spread out its mass. Together, these features have kept the structure intact and stable.

It’s “no surprise” that the pyramids resist earthquakes, says Sherif El-Tawil. But the new study offers important clues about how the pyramids have escaped damage, he says. A civil engineer at the University of Michigan in Ann Arbor, El-Tawil did not take part in this new work.

Of the ancient Seven Wonders of the World, the Great Pyramid is the last still standing. Ancient Egyptians built it in Giza around 2600 B.C. as the tomb of Pharaoh Khufu. It contains some 2.3 million stone blocks and took more than two decades to construct.

Egypt generally has low seismic activity. But it does occasionally experience strong quakes. These include a magnitude 6.8 in 1847 and a magnitude 5.9 in 1992. Such strong earthquakes can cause a lot of ground motion or vibration. Despite those powerful tremors, however, the Great Pyramid has suffered little damage.