How a gorge is created

How a gorge is formed

• Hard rock (granite which is impermeable) is under cut because of the soft rock ( limestone which is permeable) getting eroded. Freeze thaw would also take place in the joints and bedding plains which pushes the limestone into the plunge pool where hydraulic action makes the plunge pool bigger.

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• The water fall then retreats up stream because of the hard rock ledge falling away.
• Over time hydraulic action, weathering and erosion continue to cause the river to retreat up stream until a gorge is created with tall steep sides