isostaatiline

Isostatic is a term used in geology to describe the state of gravitational equilibrium between the Earth's crust and mantle such that the crust floats at an elevation commensurate with its thickness and density. This principle, known as isostasy, suggests that mountains and other elevated regions of the crust are supported by a thicker and less dense portion of the crust that extends down into the mantle. Conversely, low-lying areas are supported by thinner, denser crust.

When mass is added to the Earth's surface, such as through glaciation or the deposition of sediments, the crust subsides under the increased load. Conversely, when mass is removed, for example, through erosion or melting of ice sheets, the crust rebounds, or rises. This process of vertical adjustment is known as isostatic adjustment or isostatic rebound.

The concept of isostasy is crucial for understanding geological phenomena such as the formation of mountain ranges, the distribution of continents and oceans, and the post-glacial land uplift observed in many regions. It helps explain why different areas of the Earth's surface have varying elevations and how these elevations change over geological timescales. The balance between the buoyant force of the mantle and the weight of the crust is the fundamental principle governing this equilibrium.