Airy hypothesis

geology

Also known as: Airy model

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June 18, 2026

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The Airy hypothesis is a geological concept explaining isostasy, the balance of Earth's lithosphere as it floats on the denser asthenosphere. Proposed by Sir George Biddell Airy, it suggests that Earth's crust is a rigid shell on a more liquid substratum. This theory posits that thicker parts of the crust sink deeper, while thinner parts are buoyed up, meaning mountains have large, low-density roots extending beneath the surface, much like an iceberg floating in water. This concept was crucial in developing the theory of plate tectonics.12

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isostasy
The Airy hypothesis says that Earth’s crust is a more rigid shell floating on a more liquid substratum of greater density. Sir George Biddell Airy, an English mathematician and astronomer, assumed that the crust has a uniform density throughout. The thickness of the crustal layer is…
Read More
The Airy hypothesis says that Earth’s crust is a more rigid shell floating on a more liquid substratum of greater density. Sir George Biddell Airy, an English mathematician and astronomer, assumed that the crust has a uniform density throughout. The thickness of the crustal layer is…
Read More