Airy isostasy ($b={\rho }_{c}h/({\rho }_m-{\rho }_c)$)

A local compensation model with approximately fixed crustal density and variable crustal thickness. A height $h$ is supported by a crustal root $b={\rho }_{c}h/({\rho }_m-{\rho }_c)$ in a simple constant-density, air-loaded column model.