The deposition of alluvium (sediment) by a river(noun)
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Use "alluviation" in a sentence
"He has participated in the Sagalassos Project since 1991 and focuses on the colluviation/alluviation history, the significance of catastrophic and abrupt climatic events, and the human impact for the last 7,000 years."
"During the second week of the geomorphological survey, Etienne Paulissen and his collaborators Veronique De Laet, who grew muscles handling the Ramguts drill, and Koen Dossche, continued trying to solve the puzzle of the colluviation/alluviation history in the basin of the Aglasun Cay, to which Sagalassos belongs."
"Deforestation and intensive land use from the Hellenistic period onward seem to have initiated intense soil erosion on the hill slopes, resulting in major alluviation (up to 1.5 mm/year) so intense that the valley bottom got clogged with fine earth material creating the current landscape."