river terrace
Oxford Dictionary of Geography:
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river terrace
A bench-like feature running along a valley side, roughly parallel with the valley walls. Most terraces form when a river's erosional capacity increases so that it cuts down through its flood plain. Many river valleys have been subject to alternating phases of aggradation and dissection such that a series of terraces has developed. These are cut and fill terraces, formed as erosion alternates with deposition. Two similar terraces on each side of a river are paired terraces. These occur at times of elevation of the land surface or when downcutting is greater than lateral erosion. Unpaired terraces usually form when lateral erosion dominates.
Oxford Dictionary of Archaeology:
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river terrace
[Ge]
A platform of land formed beside a river flowing across a plain where, for some reason, the river channel has deepened and cut down to create a new flood-plain at a lower level. River terraces are often made of fluvially eroded material laid down during the creation of the flood-plain. This material sometimes includes archaeological material and faunal remains which date from any time earlier than the creation of the deposit in which they are incorporated. In this way some river terraces can be roughly dated by reference to the latest material present in the assemblages. Large river valleys usually have more than one set of terraces forming a complicated series of platforms.
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Oxford Dictionary of Geography
A Dictionary of Geography. Copyright © Susan Mayhew 1992, 1997, 2004. All rights reserved.
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