Gilbert-type delta

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Gilbert-type delta A river delta which consists of a wedge-shaped body of sediment, comprising relatively thin, flat-lying, topset sediments, long, steeply dipping foresets which prograde (see progradation) from the river mouth, and thinner, flat-lying, bottomset or toeset deposits. Gilbert-type deltas are often developed in lakes, where river water and lake water are of the same density. It was first described by the American geologist Grove Karl Gilbert (1843–1918).

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Gilbert-type delta A type of river delta which consists of a wedge-shaped body of sediment, comprising relatively thin, flatlying, topset sediments, long, steeply dipping foresets which prograde (see PROGRADATION) from the river mouth, and thinner, flat-lying, bottomset or toeset deposits. Gilbert-type deltas are often developed in lakes, where river water and lake waters are of the same density.