Final answer:
The balance between gravity and buoyancy is called isostasy.
Step-by-step explanation:
The balance between gravity and buoyancy is called isostasy. Isostasy refers to the hydrostatic equilibrium or balance between the weights of various layers in a fluid, such as the Earth's atmosphere, and the pressures that support them.
For example, in the Earth's crust and mantle, mountain ranges can be thought of as floating on the higher-density crust and mantle beneath them. This demonstrates the fluid characteristics of seemingly solid Earth.