streams Flashcards
river system
river and all its tributaries
tributary
a small stream that combines into a larger river
gradient
slope of river, rise/run
weathering
desintegration and decomposition of rock
disintegration
change in shape, broken down, physical change
decomposition
change to chemical composition, chemical change
watershed
area drained by river directly or through tributaries
divides
split up watersheds, areas of higher elevation
discharge
amount of water that flows through a river, q=va calculated by dividing the river up into smaller sections
erosion
when material is carried away
deposition
when material is dropped, placed somewhere new after being carried away
load
material eroded in a stream
solution
material dissolved in a stream
suspended load
load that is carried in the stream off the ground
bed load
load that is rolled on the bottom of a stream
competence
maximum size of sediment a stream can carry
capacity
total amount of sediment a stream can carry
base level
lowest point of a stream, lakes or oceans oceans are the lowest base level
delta
depositional areas as drains into larger areas, lakes and oceans cross sectional area widens so velocity decreases and deposition begins
cut bank
erosional area on the outside of a meander the water flows faster becaue there is less friction from the bed
point bar
depositional area, inside of meander water flows slower because of increased friction
stages of a stream
youthful: steep, v shaped valleys
mature: less steep, begins to meander
old age: low grandient, large flood plain, large meanders progesses through flooding and erosion
how do streams level up
have to join with another stream of the same level
what size of sediment depositions first?
larger sediment deposits first as it requires a higher velocity to carry
what is capacity dependent on?
velocity and discharge
levee
sediment deposited on the sides of a river
meanders
bends that form in a stream over time
v shaped valley
originally start eroding completely vertically
water then begins to weather the sides of the of the stream channel
the sediment then begins to fall in and form a v shape
stream channel
the shape of the stream itself