Fluvial processes Flashcards
What is fluvial?
Fluvial refers to the processes associated with rivers and streams and the deposits and landforms created by them
What is a river?
A river is a stream that has many tributaries.
What is a river system?
A river system is a group of streams and rivers that drain an area of land.
What is a tributary?
A tributary is a stream that flows into a larger stream/ river.
What is stream ordering?
A method of classifying types of streams based on their number of tributaries the smallest order being the first order.
What is the drainage basin?
The drainage area which contributes water to a particular channel or set of channels, river systems are divided into areas called drainage basins.
What is a divide?
Watersheds are separated from each other by an area of higher ground. Rivers on different sides of the divide flow in the opposite directions.
What are drainage patterns?
Also known as river systems, they are the patterns formed by the streams, rivers, and lakes in a particular drainage basin.
What is a dendritic pattern?
Looks like a leaf, develops relatively on uniform surface or bedrock.
What is a radial pattern?
Develops in isolated volcanic cones or domes.
What is a rectangular pattern?
Develops on high jointed bedrock, high angle junctions. Angles turns into a tributary.
What is a trellis pattern?
Develops in areas of alternating weak and resistant bedrock, small streams feed from the sides.
What is a stream channel?
A channel is the path that a stream follows, as more soil and rock are washed away, the channel gets wider and deeper. Over time, tributaries flow into the main channel of a river. The larger amount of water makes the main channel longer and wide.
What is gradient?
A measure of the change in the height of a stream over a certain distance. Gradient can be used to measure how steep a stream is.
What is discharge?
The volume of water passing a point along the river in a given amount of time.
How do you measure discharge?
Discharge= area x velocity
How do you measure velocity?
Velocity= distance (m)/ time (sec) = m/sec
What is laminar flow?
Laminar flow- water slowly flowing nearly in a straight path, the flow is smooth, the layers do not mix.
What is turbulent flow?
Water moving quickly in an erratic fashion (horizontal and vertical). Occurs when water moves in tiny circle parts as it moves downstream. Much more mixing
What is stream load?
The material carried in the stream’s water. A fast-moving stream can carry large rocks. The large rocks can cause rapid erosion by knocking away more rock and soil. A slow-moving stream carries smaller rocks in its load. The smaller particles erode less rock and soil. The stream also carries material that is dissolved in the water.
What is bed load?
Large rocks that bounce along the bottom of the stream.
What is suspended load?
Materials that are floating in the water, they often make the stream look muddy or cloudy.
What is dissolved load?
Tiny particles that dissolved in the water.
What are sinkholes?
Circular surface depressions that may be solution sinkholes formed by slow subsidence or collapse sinkholes formed in a sudden collapse through the roof of an underground cavern below.
What is the angle of repose?
The steepest angle, or slope, at which the loose material no longer moves downhill. If the slope of a pile of material is larger than the angle of repose, mass movement happens.
