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Related to isostasy: eustasy


Equilibrium in the earth's crust such that the forces tending to elevate landmasses balance the forces tending to depress landmasses.

[iso- + Greek stasis, a standstill; see stā- in Indo-European roots + -y.]

i′so·stat′ic (ī′sō-stăt′ĭk) adj.
i′so·stat′i·cal·ly adv.


(aɪˈsɒstəsɪ) or


(Geological Science) 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
[C19: iso- + -stasy, from Greek stasis a standing]
isostatic adj


or i•sos•ta•cy

(aɪˈsɒs tə si)

1. 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.
[1889; iso- + -stasy < Greek -stasia; see stasis, -y3]
i•so•stat•ic (ˌaɪ səˈstæt ɪk) adj.


the general equality of pressure in the crust of the earth. — isostatic, adj.
See also: Geology


The state of balance of the Earth’s crust as it floats on the denser mantle. Mountains are balanced by deep roots of crustal rock.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.isostasy - (geology) a general equilibrium of the forces tending to elevate or depress the earth's crust
geology - a science that deals with the history of the earth as recorded in rocks
equilibrium - a stable situation in which forces cancel one another
References in periodicals archive ?
Antarctica for which the true height of the earth surface, hidden by ice sheet and reduced by glaciation isostasy is not determinable is excluded from calculation.
2004, Global glacial isostasy and the surface of the ice-age Earth: The ICE-5G(VM2) model and GRACE: Annual Reviews of Earth and Planetary Sciences, v.
Second, Mallorca appears to be particularly well suited to the task, because neither tectonics nor isostasy - geological forces of crustal motion - over-complicate the record.
Consider a post-glacial rebound model, based on the isostasy concept, namely, that the elevation of earth's surface (over tens of millions of years) seeks a balance between the weight of lithospheric rocks and the buoyancy of the more viscous asthenosphere.
Rock-forming minerals of densities less than mantle minerals are deposited; isostasy is triggered.
Applications of isostasy and gravity methods are considered in a trio of papers.