Post-glacial rebound (sometimes called continental rebound, isostatic rebound or isostatic adjustment) is the rise of land masses that were depressed by the huge weight of ice sheets during the last ice age, through a process known as isostatic depression. It affects northern Europe, especially Scotland and Scandinavia, Siberia and Canada.
Certain areas (such as the Himalayas) are not in isostatic equilibrium, which has forced researchers to identify other reasons to explain their topographic heights (in the case of the Himalaya, by proposing that their elevation is being "propped-up" by the force of the impacting Indian plate).
In the simplest example, isostasy is the principle observed by Archimedes in his bath, where he saw that when an object was immersed, an amount of water equal in volume to that of the object was displaced.
Conversely, isostatic post-glacial rebound is observed in areas once covered by ice-sheets which have now melted, such as around the Baltic Sea and Hudson Bay.
The global process of glacial isostatic adjustment (GIA) is the process whereby the Earth's shape and gravitational field are modified in response to the large scale changes in surface mass load that have attended the glaciation and deglaciation of the planetary surface.
A further influence upon the glacial isostatic adjustment process that has recently been investigated concerns the feedback of the changing rotational state of the planet caused by the glaciation and deglaciation process upon the variations of sea level that occur during the GIA process.
Glacial isostatic adjustment and earth rotation: refined constrains on the viscosity of the deepest mantle, J. Geophys.
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