Back to Erosion Landform
- An exhumed river channel is a ridge of sandstone.
- That remains softer flood plain mudstone is eroded away.
- The process begins;
1.The deposition of sand withine river channel.
2.Then mud on the adjacent floodplain.
3.Eventually channel is abandoned.
4.After buried flood deposits from other channels.
5.Groundwater flows easily.
- Minerals (calcium carbonate) can cement the grains together.
- It converting the loose sand into sandstone.
- Pressure from overlying sediments compresses the floodplain mud.
- It converting it to mudstone.
- Millions of years later, erosion can remove softer, less cemented mudstone.
- It leave the more resistant sandstone as a sinuous ridge.
- An exhumed river channel is a form of inverted relief.
- Exhumed channels are important indicators for ancient stream flow direction.
- Examples of exhumed river channels;
-Cretaceous Cedar Mountain Formation ,Green River, Utah.