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| Abrasion is mechanical scraping of a rock surface by friction between rocks and moving particles during their transport in wind, glacier, waves, gravity or running water, after friction, the moving particles dislodge loose and weak debris from the side of the rock, these particles can be dissolved in the water source. |
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| A fan-shaped wedge of sediment that typically accumulates on land where a stream emerges from a steep canyon onto a flat area. In map view it has the shape of an open fan. Typically forms in arid or semiarid climates. |
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| The lower limit of erosion by a stream. Sea level is the ultimate base level. However, lakes can serve as a temporary base level in upstream areas. |
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| The larger, heavier particles that are being transported by a stream. Instead of being dissolved or suspended, these are being rolled or bounced along, spending at least part of their time in contact with the stream bottom. |
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the amount of a stream is indicated by both amount of sediments and size of the particals being moved in the stream. |
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| A deposit of sediment that forms where a stream enters a standing body of water such as a lake or ocean. The name is derived from the Greek letter "delta" because these deposits typically have a triangular shape in map view. |
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| The volume of water in a flowing stream that passes a given location in a unit of time. Frequently expressed in cubic feet per second or cubic meters per second. Calculated by the formula Q = A x V where Q is the discharge, A is the cross sectional area of the channel and V is the average velocity of the stream. |
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| A ridge that separates two adjacent drainage basins. |
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| The geographic area that contributes runoff to a stream. It can be outlined on a topographic map by tracing the points of highest elevation (usually ridge crests) between two adjacent stream valleys. Also referred to as a "watershed". |
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| An overflow of water onto lands that are normally above local water levels. Can be caused by stream discharge exceeding the capacity of the stream channel, storm winds and reduced pressure drawing water from a lake or ocean onto the coastline, dam failure, lake level increase, local drainage problems or other reasons. |
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| An area of alluvium-covered, relatively level land along the banks of a stream that is covered with water when the stream leaves its channel during a time of high flow. |
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| A gully is a landform created by running water eroding sharply into soil, typically on a hillside. Gullies resemble large ditches. |
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| Headward erosion is a fluvial process of erosion that lengthens a stream, a valley or a gully at its head and also enlarges its drainage basin. |
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| A long continuous ridge built by people along the banks of a stream to contain the water during times of high flow. Natural levees can also be built along the banks of a stream. When the flood water decelerates upon leaving the channel, sediments quickly drop out of suspension and build a ridge over time. |
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| A stream that has many bends (meanders). This type of drainage pattern usually develops on a nearly level landscape and where the banks of the stream are easily eroded. |
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| A crescent-shaped lake that forms when a meandering stream changes course. Such changes in course frequently occur during flood events when overbank waters erode a new channel. |
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| A cylindrical or hemispherical hold in the bedrock of a stream that is formed from the continual swirling motion of sand and gravel by swirling currents. |
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| A chemical weathering process in which a material is dissolved. Also, the transport of dissolved ions by the water of a stream. |
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| Capture effected by the lateral planation of a stream invading and diverting the upper part of a smaller stream. |
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| Tiering of benthic marine suspension-feeding communities on soft substrata has varied throughout the Phanerozoic. |
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| A water gap is an opening or notch which flowing water has carved through a mountain range. |
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