Questions and Answers
Where do waterfalls form?
The upper course
Where do waterfalls form (site)?
Waterfalls form in upper course areas where there is an increase in vertical erosion, where there is a layer of cap rock overlaying a softer, less resistant rock.
What physical processes undercut hard rock?
Over time hydraulic action and abrasion erode soft rock more quickly, undercutting hard rock.
What happens when hard rock is left overhanging?
Signup and view all the answers
How is the plunge pool eroded?
Signup and view all the answers
Why does a waterfall move upstream?
Signup and view all the answers
How is a steep-sided gorge formed?
Signup and view all the answers
Explain how waterfalls form:
Signup and view all the answers
Study Notes
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.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Test your knowledge on how waterfalls are formed with these flashcards. Each card explores the processes and locations where waterfalls typically occur. Perfect for students studying geology or physical geography.