17 articles
Aggradation
Aggradation is the raising of a land surface, most often a river bed or floodplain, through net sediment deposition, occurring when sediment supply exceeds a river's transport capacity.
Base level
Base level is the lowest elevation to which a stream can erode its bed, a fundamental concept in fluvial geomorphology defined by John Wesley Powell in 1875.
Bedload
Bedload is the part of a stream's sediment load that moves by sliding, rolling, or skipping on or very near the streambed, generally much less than the suspended load.
Braided river
A braided river is a river that flows in multiple, mobile channels separated by temporary bars and islands, one of three classic channel patterns alongside meandering and straight.
Channelization
Channelization is the engineering modification of a river or stream so its flow follows a fixed, controlled course, typically by straightening, deepening, or lining the channel.
Crevasse splay
A crevasse splay is a fan-shaped deposit of sand and mud on a floodplain, formed where floodwater escapes through a breached river levee and can eventually trigger an avulsion.
Distributary channel
A distributary channel is a stream branch carrying water and sediment away from a main channel rather than adding to it as a tributary does, forming river deltas.
Drainage density
Drainage density is a measure of how finely a landscape is dissected by stream channels: the total stream length in a drainage basin divided by its area, first formalized by Robert E. Horton in 1932.
Gravel-bed river
A gravel-bed river is an alluvial river whose bed is gravel and cobble, 2 to 256 mm, common in steep mountain terrain, where sediment moves mainly as bedload.
Incised valley
An incised valley is a valley cut by a river into coastal-plain strata after a sea-level fall, later filled with sediment during renewed sea-level rise.
Long profile
A long profile of a river is a plot of channel elevation against distance downstream, a diagnostic of tectonic uplift, rock resistance, and base level changes.
Point bar
A point bar is a sediment deposit built on the inside of a river bend where slower water drops its load, a defining feature of meandering rivers.
River bed
River bed: the floor of a river channel, normally covered by water, made of alluvium or bedrock. Shaped by erosion, transport, and deposition; bankfull flows maintain it, and fine-sediment clogging degrades its habitat.
River delta
River delta: landform of riverborne sediment deposited at the edge of an ocean or lake; classified by Galloway as river-, wave-, or tide-dominated; 40 large deltas studied show subsidence often exceeding sea-level rise.
Stream capture
Stream capture, also called river capture or stream piracy, is the natural diversion of a stream's water into a neighboring drainage basin, reorganizing river networks.
Stream power
Stream power is the rate at which a river expends energy, especially in transporting its sediment load, and underlies sediment transport theory, channel classification, and models of river incision.
Suspended load
Suspended load is the part of a river's sediment load supported by turbulence and carried downstream at roughly the water's velocity, unlike bedload, which moves along the streambed.