eustasy

hydrology

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June 26, 2026

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Eustasy refers to a worldwide change in sea level. This is distinct from local changes in land elevation due to geological forces. Global sea level has fluctuated significantly throughout Earth's history, dropping dramatically between 30,000 and 15,000 years ago and rising since then.123

Current sea level rise is driven by melting glaciers and ice sheets, and the thermal expansion of ocean water as it absorbs heat. These factors contribute to increased coastal flooding, storm surges, and erosion, impacting populations, ecosystems, and economies. The rate of sea level rise has accelerated in recent decades.45

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continental margin
Margin types
…changes in sea level, called eustatic sea-level changes, have occurred throughout geologic history. The most common causes of such sea-level changes are global climatic fluctuations that lead to major glacial advances and retreats—that is, ice ages and interglacial periods. Other causes that are not as well understood may include major…
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…changes in sea level, called eustatic sea-level changes, have occurred throughout geologic history. The most common causes of such sea-level changes are global climatic fluctuations that lead to major glacial advances and retreats—that is, ice ages and interglacial periods. Other causes that are not as well understood may include major…
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coral reef
Origin and development of reefs
…either by uplift or by eustatic regression of the sea (which is determined by ice sheet–sea level relations), is subject to planing by marine erosion. If planing off is complete, a flat-topped submerged platform results. If subsidence or eustatic submergence intervenes, a wave-cut terrace is left around the reef. Terraces…
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…either by uplift or by eustatic regression of the sea (which is determined by ice sheet–sea level relations), is subject to planing by marine erosion. If planing off is complete, a flat-topped submerged platform results. If subsidence or eustatic submergence intervenes, a wave-cut terrace is left around the reef. Terraces…
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