Describe the concept of isostatic equilibrium. What will be an ideal response?

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Any part of a continent that projects above sea level must be supported within the
asthenosphere in the same way that an iceberg or a ship floats on water. Buoyancy enables an
object to float in a fluid by displacing a volume of that fluid equal in weight to the floating
object’s own weight. Consider the continent that contains Mount Everest, the highest of
Earth’s mountains at 8.84 kilometers (29,007 feet) above sea level. Mount Everest and its
neighboring peaks are not supported by the mechanicalstrength of the materials within Earth;
nothing in our world is that strong. Over a long period, and under the tremendous weight of
the overlying crust, the asthenosphere behaves like a dense, viscous, slowly moving fluid.
The continent’s mountains float high above sea level because the lithosphere gradually sinks
into the deformable asthenosphere until it has displaced a volume of asthenosphere equal in
mass to the mountains’ mass. The mountains stand at great height, nearly in balance with
their subterranean underpinnings but susceptible to rising or falling as erosion or crustal
stresses dictate. In a slow-motion version of a ship floating in water, the entire continent stands in isostatic equilibrium.