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Icebergs off the coast of Antarctica. Melting ice can lead to eustasy.

A back-formation from eustatic (borrowed from German eustatische (eustatic), from Ancient Greek εὖ (, well, good) + στάσις (stásis, standing))[1] +‎ -y.



eustasy (plural eustasies)

  1. (geology, oceanography) A worldwide change in sea level, especially one caused by melting ice or tectonic activity. [from 1940s]
    • 1946, The Journal of the Anthropological Institute of Great Britain and Ireland, volume 76–77, London: The Royal Anthropological Institute of Great Britain and Ireland, ISSN 0307-3114, OCLC 1334521, page 116, column 1:
      The age of the dunal or other deposits, formed on it after the sea had begun to withdraw, in accordance with the theory of glacial eustasy, and which I have named Berardian, is, however, the crucial thing here.
    • 1965, Horace G. Richards; Rhodes W[hitmore] Fairbridge, Annotated Bibliography of Quaternary Shorelines (1945–1964): Prepared for the VII International Congress of International Association for Quaternary Research (INQUA) Meeting at Boulder, Colorado, August 30 – September 5, 1965 (Special Publication; 6), Philadelphia, Pa.: Academy of Natural Sciences, OCLC 499347407, page 250:
      Takai, F., and Tsuchi, R. 1963 The Quaternary: In "Geology of Japan," Univ. Calif. Press: 173–196 / [] From these facts, it is inferred that the main coastal terraces were probably formed due to glacial eustacy.
    • 1968, Asian Perspectives: A Journal of Archaeology and Prehistory of Asia and the Pacific, volume 12, Honolulu, Hi.: University Press of Hawaii, ISSN 0066-8435, OCLC 755911170, page 133, column 2:
      The range in elevation suggests that the sea level was not constant during the formation of the caves and that the rise of land – perhaps counterbalanced periodically by glacial eustacies – was probably continuous.
    • 1993, Stephen M. Greenlee; Patrick J. Lehmann, “Stratigraphic Framework of Productive Carbonate Buildups”, in Robert G. Loucks and J. Frederick Sarg, editors, Carbonate Sequence Stratigraphy: Recent Developments and Applications (AAPG Memoir; 57), Tulsa, Okla.: The American Association of Petroleum Geologists, →ISBN, abstract, page 43:
      Although the origin of these long-term accommodation changes is difficult to assess, we conclude that basin tectonism is responsible for these changes in most of our examples. Long-term eustasy plays a secondary role, according to our analysis.
    • 2015, M. P. Cooper; J[ohn] E. Mylroie, “Pseudokarst and Non-dissolutional Caves”, in Glaciation and Speleogenesis: Interpretations from the Northeastern United States (Cave and Karst Systems of the World), Cham, Switzerland: Springer International Publishing AG Switzerland, DOI:10.1007/978-3-319-16534-9_4, →ISBN, part II (Cave and Karst Regions of the Northeastern US), abstract, page 49:
      Glaciation, by oversteepening slopes, and by subsequent isostatic rebound, greatly enhances crevice cave and talus cave formation. Glacial eustasy and isostatic rebound form, and then preserve, sea caves.
    • 2016, John K. Warren, “Subaqueous Salts: Salinas and Perennial Lakes”, in Evaporites: A Geological Compendium, 2nd edition, Cham, Switzerland: Springer International Publishing AG Switzerland, DOI:10.1007/978-3-319-13512-0, →ISBN, page 380:
      In summary, because modern continental settings lack a hydrology suitable for supplying huge volumes of brine, sufficient to form a megasalt deposit, neither modern sabkhas or salinas are directly relevant to the formation of the hydrologies and eustasies needed to deposit the huge masses of ancient marine-fed subaqueous salts detailed in Chap. 5.

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