How isostasy works?

Isostasy is the geological principle that explains how the Earth's crust maintains equilibrium on the underlying mantle. It operates on the concept that the Earth's lithosphere "floats" at an elevation that depends on its thickness and density. When large masses, such as mountains or ice sheets, are added or removed, the crust adjusts by rising or sinking to restore balance. This process can take thousands to millions of years, reflecting the dynamic nature of the Earth's surface.