Waterfall Formation Flashcards

Waterfall Formation Overview

• Waterfalls typically form in the upper course of rivers.
• They occur where vertical erosion increases, particularly where hard, resistant cap rock overlays softer rock.

Erosion Processes

• Hydraulic action and abrasion are two key processes that undercut hard rock.
• Soft rock erodes more rapidly, leading to undercutting of the harder layer.

Overhanging Rock Collapse

• As undercutting progresses, the hard rock may become overhanging.
• Lack of support eventually leads to the collapse of the overhanging hard rock.

Plunge Pool Erosion

• When rocks fall into the plunge pool, they create more erosion through hydraulic action and corrasion.
• This ongoing process enhances the depth and shape of the plunge pool.

Upstream Movement of Waterfall

• As the waterfall continues to erode the surrounding landscape, it gradually migrates upstream.
• The repeated erosion and collapse process causes this retreat of the waterfall.

Formation of Steep-Sided Gorges

• A steep-sided gorge forms as the waterfall retreats due to continually repeated undercutting.
• This geological feature showcases the effects of persistent erosion over time.

Example of Waterfalls

• Angel Falls in Venezuela serves as a notable example of waterfall formation, illustrating the principles discussed.