THEORY OF ISOSTASY
The term Isostasy was coined by the American geologist “Clarence Dutton” in
1882.
The theory of Isostasy explains how different topographic heights can exist on
the earth’s surface. It states that the Earth’s crust floats on the top of the
denser mantle. The crust’s elevation depends on its thickness and density.
Higher regions like mountains have thicker crust and extended deeper into the
mantle. While on the other hand, Lower regions like Oceans basins have a
thinner crust. This ensure the continent and oceans are at a state of
equilibrium, [akin to buoyancy].
The theory of Isostasy can be compared to a boat floating in water with less
mass and more density.
There are two views in Isostasy.
Pratt’s Isostasy:
1. British geologist “John Henry Pratt’s” took an alternative method to
explain isostatic equilibrium.
2. Pratt’s hypothesis is based on the density of the lithospheric blocks
rather than their thickness.
3. Similarly in the Pratt Isostasy less dense portions of the earth’s crust
[such as those made of less dense rock types or those underlain by
substantial sedimentary deposits] ‘float’ higher on the denser mantle.
The term Isostasy was coined by the American geologist “Clarence Dutton” in
1882.
The theory of Isostasy explains how different topographic heights can exist on
the earth’s surface. It states that the Earth’s crust floats on the top of the
denser mantle. The crust’s elevation depends on its thickness and density.
Higher regions like mountains have thicker crust and extended deeper into the
mantle. While on the other hand, Lower regions like Oceans basins have a
thinner crust. This ensure the continent and oceans are at a state of
equilibrium, [akin to buoyancy].
The theory of Isostasy can be compared to a boat floating in water with less
mass and more density.
There are two views in Isostasy.
Pratt’s Isostasy:
1. British geologist “John Henry Pratt’s” took an alternative method to
explain isostatic equilibrium.
2. Pratt’s hypothesis is based on the density of the lithospheric blocks
rather than their thickness.
3. Similarly in the Pratt Isostasy less dense portions of the earth’s crust
[such as those made of less dense rock types or those underlain by
substantial sedimentary deposits] ‘float’ higher on the denser mantle.
