The thin lithospheric plates which cover the surface of the Earth are also subject to flexure, when a load or force is applied to them. On a geological timescale, the lithosphere behaves, elastically (in first approach) and can therefore bend under loading by mountain chains, volcanoes and so on.
The flexure of the plate depends on:
1. The plate thickness (usually referred to as elastic thickness of the lithosphere).
2. The elastic properties of the plate
3. The applied load or force
As flexural rigidity of the plate is determined by the Young's modulus, Poisson's ratio and cube of the plates elastic thickness, it is a governing factor in both (1) and (2).