Rivers Flashcards
What are the names of a rivers courses?
lower course
middle course
upper course
What is a drainage basin?
an area of land where water from rain or snow melt drains downhill into a body of water such as a river
What is a watershed?
the area of high land forming the edge of a river basin.
What is a long profile of a river?
a way of displaying the channel slope (gradient) of a river along its entire length
3 types of cross profile of river?
.V shaped valley (steep sided - narrow shallow)
.floodplain (wider, flat - wide and deep)
.levees (very wide and flat - wide and deep)
Why does gradient of a river change along its long profile?
shows a steep upper course as this section is in upland areas made of hard rock
middle and lower course the land becomes flatter because rock around is softer.
What is cross profile of a river?
a section taken sideways across the channel or valley
What is channel depth?
downstream change, reason
how deep the channel is
↑ river deep due to erosion - more water added by tributaries
What is channel depth?
downstream change and reason
how wide channel is
↑ rock erodes away at lower course- rock is softer
What is gradient of a river?
downstream change, reaosn
how steep the channel is
↓ land further down is flatter because rock softer as go down
What is load quantity?
downstream change, reason
average amount of sediment
↑ faster water can erode more material and carry more material
What are fluvial processes?
term given to processes that shape our rivers
What is the velocity of a river?
downstream change, reason
speed of the water
↑ friction lower in lower course because river is wider, deeper and smoother
What is load size?
downstream change, reason
average size of sediment and point of river
↓ attrition means sediment is eroded into smaller sediment - goes downstream
What is channel bed roughness?
downstream change, reason
amount of friction between river bed and water
↓ abrasion means river bed will be eroded to smoother downstream where velocity is higher.
What is discharge of a river?
downstream change, reason
volume of water flowing through the river
↑ water added by tributaries, water is travelling faster, rivers are wider and deeper
What is Hydraulic action (river)?
power or water eroding river bed and banks
What is abrasion (river)?
rocks carried along river wear down bed and banks