Showing posts with label Geography of Fluvial Landforms. Show all posts
Showing posts with label Geography of Fluvial Landforms. Show all posts

Friday, October 6, 2017

Fluvial Landforms

Fluvial landforms result from erosion by water flowing on land surfaces. Fluvial landforms include the following:

• ait—a small island in a river.
• alluvial fan—a fan-shaped deposit formed where a fast-flowing stream flattens, slows, and spreads, typically at the exit of a canyon onto a flatter plain.
• anabranch—a section of a river or stream that diverts from the main channel or stem of a watercourse and rejoins the main stem downstream.
• arroyo—usually dry creek bed or gulch that temporarily (or seasonally) fills with water after a heavy rain.
• bayou—a small, slow-moving stream or creek, or a lake or pool that lies in an abandoned channel of a stream.
• braided river—one of a number of channel types and has a channel that consists of a network of small channels separated by small and often temporary islands called braid bars.
• Carolina Bay—elliptical depressions concentrated along the Atlantic seaboard within coastal Delaware, Maryland, New Jersey, Virginia, Georgia, North Carolina, South Carolina, and north-central Florida.
• drainage basin—an extent of land where water from rain or snowmelt drains downhill into a body of water, such as a river, lake, reservoir, estuary, wetland, sea, or ocean.
• exhumed river channel—a ridge of sandstone that remains when the softer floodplain mudstone is eroded away.
• gully—landform created by running water eroding sharply into soil, typically on a hillside.
• lacustrine plain—a plain that originally formed in a lacustrine environment, that is, as the bed of a lake from which the water has disappeared, by natural drainage, evaporation, or other geophysical processes.
• lake—a terrain feature, a body of liquid on the surface of a world that is localized to the bottom of a basin and moves slowly if it moves at all.
• levee—a natural or artificial slope or wall to regulate water levels.
• meander—a bend in a sinuous watercourse.
• oasis—an isolated area of vegetation in a desert, typically surrounding a spring or similar water source.
• oxbow lake—a U-shaped body of water formed when a wide meander from the mainstem of a river is cut off to create a lake.
• pond—a body of water smaller than a lake.
• proglacial lake—a lake formed either by the damming action of a moraine or ice dam during the retreat of a melting glacier or by meltwater trapped against an ice sheet due to isostatic depression of the crust around the ice.
• rapid—a section of a river where the riverbed has a relatively steep gradient causing an increase in water velocity and turbulence.
• riffle—a shallow stretch of a river or stream, where the current is below the average stream velocity and where the water forms small rippled waves as result.
• rock-cut basin—cylindrical depressions cut into stream or riverbeds, often filled with water.
• spring—any natural occurrence where water from below the surface of the Earth flows onto the surface of the Earth and is thus where the aquifer surface meets the ground surface.
• stream—a flowing body of water with a current, confined within a bed and stream banks.
• stream terrace—relict feature, such as a floodplain, from periods when a stream was flowing at a higher elevation and has downcut to a lower elevation.
• swamp—a wetland featuring temporary or permanent inundation of large areas of land by shallow bodies of water.
• wadi—Arabic term traditionally referring to a valley.
• waterfall—a body of water resulting from water, often in the form of a stream, flowing over an erosion-resistant rock formation that forms a nickpoint, or sudden break in elevation.