Glacial isostatic adjustment

Glacial isostatic adjustment (GIA) is the process by which the Earth’s crust adjusts to the melting of glaciers and ice sheets that previously covered large areas of the planet during ice ages. When these ice masses were present, they caused the Earth’s crust to be depressed under their immense weight.

As the glaciers melted, the land beneath them started to rebound, gradually rising back to its original position. This process occurs over thousands of years and is still ongoing in areas that were once glaciated, even if the glaciers themselves have long disappeared.

GIA has significant geological and environmental implications, affecting coastal regions and sea levels, as well as influencing the Earth’s crustal movements and seismic activity in these areas. Scientists study GIA to understand its impact on the Earth’s surface and to make predictions about future changes in land and sea levels.

Around 20,000 years ago, during the Last Glacial Maximum, large ice sheets covered significant portions of North America, Europe, and Asia. These ice sheets exert tremendous pressure on the Earth’s crust.

The Earth is not a perfect sphere. The planet’s irregular topography and mass distribution can be described as a surface called a geoid, which is shown here with colors and exaggerated heights from multiple points of view. Developing an accurate geoid is essential for enabling global mapping and navigation.

Source: https://timeandnavigation.si.edu/multimedia-asset/geoid

Atlantis sank around 14,000 years ago

The sudden disappearance of ice around 14,000 years ago did lead to significant land uplift in regions that were previously glaciated, including parts of North Europe. As the massive ice sheets melted, the land beneath them started to rebound in a process known as glacial isostatic adjustment (GIA). This rebounding caused the land to rise, pushing parts of North Europe up.

Conversely, as the land rose, it likely had an effect on the adjacent areas, including parts of the Atlantic Ocean. The rise in land could have contributed to the subsidence (sinking) of the adjacent oceanic crust. This complex interplay between land uplift and oceanic crust subsidence can influence sea levels and the shape of coastlines, affecting the geography of regions near former ice sheets.

Could the land surface in Northern Europe that was pushed down because of the massive ice sheets, cause a land surface rise in the Atlantic Ocean?

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