The elastic thickness of the lithosphere (Te): meaning and use

To provide a basis for a physically consistent unified interpretation of the observed variations of Te for continental and oceanic lithosphere, the authors developed an analytical and numerical approach that allows direct treatment of Te in terms of the lithospheric rheology, thermal structure, and strain/stress distribution. The technique is based on finding true inelastic and equivalent (effective) elastic solutions for the problem of deformation of the lithosphere with realistic brittle-elasto-ductile rheology. It is shown that the thermal state (thermotectonic age) of the lithosphere is only one of at least three equally important properties that determine apparent values of Te. These other properties are the state of the crust-mantle interface (decoupling of crust and mantle), the thickness and proportions of the mechanically competent crust and mantle, and the local curvature of the plate, which is directly related to the bending stresses.