Definition of eustasy in English:



mass noun
  • A change of sea level throughout the world, caused typically by movements of parts of the earth's crust or melting of glaciers.

    • ‘Coastal ecosystems have been forced to migrate staggering distances since the waning of Pleistocene glaciers began to drive the postglacial rise in global sea level, termed eustasy by geologists.’
    • ‘Within this rhythm, alternations between PDF and WDF units record the interplay between sediment supply, basin subsidence, climate and eustasy, which caused repeated minor progradational and retrogradational rhythms.’
    • ‘Moreover, glacial eustasy is rejected because of the lack of evidence for widespread glaciation at the appropriate stratigraphic level and because the required kilometre-scale drawdown far exceeds that expected through glaciation.’
    • ‘Such variables, on a shallow marine carbonate platform developed upon a passive margin, are essentially represented by eustasy, climate, subsidence and sedimentation rate.’
    • ‘Such changes are not as rapid as those associated with glacio and geoidal eustasy but over a prolonged time period (perhaps longer than the Quaternary) they could have had a major impact on the level of the world's oceans.’


1940s back-formation from eustatic, coined in German from Greek eu ‘well’ + statikos ‘static’.