A gently sloping apron of sediment dropped by an ephemeral stream at the base of a mountain in arid or semi-arid regions.
The likelihood, expressed as a percentage, that an event (e.g., a flood of a given size) will happen in a given year.
A stream that cuts across an uplifted mountain range; the stream must have existed before the range uplifted and must then have been able to downcut as fast as the land was rising.
(1) A sheet or elongate lens or mound of alluvium; (2) a unit of air pressure measurement approximately equal to 1 atm.
The ability of flowing water to carry sediment, as represented by the largest clast size that the stream can transport.
A wedge of sediment formed at a river mouth when the running water of the stream enters standing water, the current slows, the stream loses competence, and sediment settles out.
The process in which water flowing through a channel cuts into the substrate and deepens the channel relative to its surroundings.
A stream whose bed lies above the water table, so that the stream flows only when the rate at which water enters the stream from rainfall or meltwater exceeds the rate at which water infiltrates the ground below.
A flood that occurs during unusually intense rainfall or as the result of a dam collapse, during which the floodwaters rise very fast.
An event during which the volume of water in a stream becomes so great that it covers areas outside the stream's normal channel.
The process by which a stream channel lengthens up its slope as the flow of water increases.
A cross-sectional image showing the variation in elevation along the length of a river.
A pair of low ridges that appear on either side of a stream and develop as a result of the accumulation of sediment deposited naturally during flooding.
A stream that flows year-round because its bed lies below the water table, or because more water is supplied from upstream than can infiltrate the ground.
A reach of a stream in which water becomes particularly turbulent; as a consequence, waves develop on the surface of the stream.
Floods that appear almost every year during seasons when rainfall is heavy or when winter snows start to melt.
A film of water less than a few millimeters thick that covers the ground surface during heavy rains.
The situation in which headward erosion causes one stream to intersect the course of another, previously independent stream, so that the intersected stream starts to flow down the channel of the first stream.
The reed downcutting of a stream into a floodplain or peneplain, caused by a relative drop of the base level.
A flat surface, underlain by alluvium, that borders a stream; terraces form when the stream cuts down into the alluvium that it had deposited previously.
A stream whose geometry has been laid down on a rock structure and is not controlled by the structure.
A valley whose cross-sectional shape resembles a V; the valley probably has a river running down the point of the V.