Lithosphere-Asthenosphere boundary a thermal control of oceanic-lithosphere thickness. The continental lithosphere contains an ancient, stable part known as the craton. The LAB is particularly difficult to study in these regions and evidence suggests that the lithosphere within this old part of the continent is at it thickest and even appears to exhibit large variations in thickness beneath the cratons, thus supporting the theory that lithosphere thickness and LAB depth are age-dependent. Depths of the LAB beneath these regions (also known as shields and platforms) are estimated to be between 200 and 250 km deep. Beneath Phanerozoic continental crust, the LAB is roughly
Expanding Earth of action. During the 1960s, the theory of plate tectonics—initially based on the assumption that Earth's size remains constant, and relating the subduction zones to burying of lithosphere at a scale comparable to seafloor spreading—became the accepted explanation in the Earth Sciences. The scientific community finds that significant evidence contradicts the Expanding Earth theory, and that evidence used in support of it is better explained by plate tectonics: Expanding Earth The expanding Earth or growing Earth hypothesis asserts that the position and relative movement of continents is at least partially due to the volume of Earth increasing. Conversely, geophysical global