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Upper Course
- River uses its energy to erode and transport bed load
- There is very little deposition due to rapid river flow
- River flows across steep ground which gives it a lot of energy and a high velocity
- This allows the river to transport large boulders
- The river erodes through Hydraulic action and abrasion
- The river is shallow and the banks are resistant to erosion so most erosion is vertical, forming a v-shaped valley
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Middle course
- Gradient decreases so velocity and energy decrease
- Smaller energy can only transport only smaller bed load- sand and silt
- River erodes at outer banks of meanders where velocity is greatest
- Deposits on inner bank where velocity is slower
- River banks are less rocky and erosion is lateral, forming meanders and flood plains
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Lower course
- Transports mainly suspended load
- Main process is deposition
- Land is almost flat so velocity and energy very small
- Only transpots tiny material (silt and clay) in suspension causing water to look brown
- Large meanders develop through lateral erosion and ox-bow lakes form in easily eroded ares
- Deposited material across river bank forms levees
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