Sound (geography)

In geography, a sound is a large sea or ocean inlet larger than a bay, deeper than a bight, and wider than a fjord; or a narrow sea or ocean channel between two bodies of land (see also strait).

There is little consistency in the use of "sound" in English-language place names.

A sound is often formed by the sea's flooding a river valley. This produces a long inlet where the sloping valley hillsides descend to sea-level and continue beneath the water to form a sloping sea floor. The Marlborough Sounds in New Zealand are a good example of this type of formation.

Sometimes a sound is produced by a glacier's carving out a valley on a coast then receding, or the sea's invading a glacier valley. The glacier produces a sound that often has steep, near vertical sides that extend deep under water. The sea floor is often flat and deeper at the landward end than the seaward end, due to glacial moraine deposits. This type of sound is more properly termed a fjord (or fiord). The sounds in Fiordland, New Zealand, have been formed this way.

A sound generally connotes a protected anchorage.

In the more general northern European usage, a sound is a strait or the most narrow part of a strait. In Scandinavia and around the Baltic Sea, there are more than a hundred straits named Sund, mostly named for the island they separate from the continent or a larger island.

In contrast, the Sound is the internationally recognized, short name for the Øresund, the narrow stretch of water that separates Denmark and Sweden, and is the main waterway between the Baltic Sea and the North Sea. It is also a colloquial short name, among others, for Plymouth Sound, England.

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