St. Anna Trough

geographical feature, Arctic Ocean

Also known as: Svyataya Anna Trough, Svyatoy Anny

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Last updated

July 13, 2026

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The St. Anna Trough is a significant underwater feature within the Arctic Ocean. It is the largest of several submarine valleys found along the Eurasian continental shelf, stretching 300 miles long and 110 miles wide. This trough is part of the broader North Polar Basin, which is characterized by extensive continental shelf extensions. The Arctic Ocean itself is the world's smallest ocean, centered around the North Pole, and is known for its remoteness, harsh weather, and ice cover. While deep-sea trenches are typically formed by tectonic plate subduction and reach extreme depths, the St. Anna Trough is a glacial trough, shaped by past glacial activity.1234

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Kara Sea
…by two wide, deep-sea troughs—the Svyatoy Anny east of Franz Josef Land, with a depth of 2,034 feet (620 metres), and the parallel Voronin Trough, some 180 miles (290 km) east, with a depth of 1,475 feet (450 metres). East of Novaya Zemlya stretches the Novaya Zemlya Trough, 650–1,300 feet…
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…by two wide, deep-sea troughs—the Svyatoy Anny east of Franz Josef Land, with a depth of 2,034 feet (620 metres), and the parallel Voronin Trough, some 180 miles (290 km) east, with a depth of 1,475 feet (450 metres). East of Novaya Zemlya stretches the Novaya Zemlya Trough, 650–1,300 feet…
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Arctic Ocean
Topography of the ocean floor
The largest of these, the Svyataya Anna Trough, is 110 miles wide and 300 miles long.
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The largest of these, the Svyataya Anna Trough, is 110 miles wide and 300 miles long.
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