isostasy

American  

[ahy-sos-tuh-see] / aɪˈsɒs tə si /

Or isostacy

noun

1. Geology. the equilibrium of the earth's crust, a condition in which the forces tending to elevate balance those tending to depress.

2. the state in which pressures from every side are equal.

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isostasy British  

/ ˌaɪsəʊˈstætɪk, aɪˈsɒstəsɪ /

noun

1. the state of balance, or equilibrium, which sections of the earth's lithosphere (whether continental or oceanic) are thought ultimately to achieve when the vertical forces upon them remain unchanged. The lithosphere floats upon the semifluid asthenosphere below. If a section of lithosphere is loaded, as by ice, it will slowly subside to a new equilibrium position; if a section of lithosphere is reduced in mass, as by erosion, it will slowly rise to a new equilibrium position

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isostasy Scientific  

/ ī-sŏs′tə-sē /

1. Equilibrium in the Earth's crust, in which an elevated part in one area is counterbalanced by a depressed part in another. Isostasy exists because the Earth's crust is relatively light compared to the denser mantle over which it lies, and therefore behaves as if it is floating. Areas of the Earth's crust rise or subside to accommodate added load (as from a glacier) or diminished load (as from erosion), so that the forces that elevate landmasses balance the forces that depress them.

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Other Word Forms

• isostatic adjective

Etymology

Origin of isostasy

1885–90; iso- + -stasy < Greek -stasia; stasis, -y ³

Example Sentences

In the context of isostasy, what would prevent an area of continental crust from becoming part of an ocean?

From Textbooks • Jan. 1, 2015

There are many problems with the land-bridge theory, one being that it is completely inconsistent with isostasy, and another that there is no evidence of the remnants of the land bridges.

From Textbooks • Jan. 1, 2015

Theory holds that the mantle is able to convect because of its plasticity, and this property also allows for another very important Earth process known as isostasy.

From Textbooks • Jan. 1, 2015

To isostasy, these lines: What is it rules the upper crust?

From Time Magazine Archive

The process of vertical movement known as isostasy, was a foundation of geological beliefs for generations, though no one had any good theories as to how or why it happened.

From "A Short History of Nearly Everything" by Bill Bryson