Diluvium is an archaic term applied during the 1800s to widespread surficial deposits of sediments that could not be explained by the historic action of rivers and seas. Diluvium was initially argued to have been deposited by the action of extraordinary floods of vast extent, specifically the Noachian Flood.

In 1822 and 1823, William Buckland published the term diluvium in his monograph Reliquiae Diluvianae and in G. A. Mantel's monograph about the