Coastal geomorphic processes and geology


Published on

GCSE Geography Coastal geomorphic processes and geology for OCR B controlled assessment

Published in: Education, Technology
1 Like
  • Be the first to comment

No Downloads
Total views
On SlideShare
From Embeds
Number of Embeds
Embeds 0
No embeds

No notes for slide

Coastal geomorphic processes and geology

  1. 1. Exam Q • Including keywords where possible, describe and explain how erosion can influence the coast. You may use a diagram. [3marks]
  2. 2. Recap: What are the 4 Types of coastal erosion?
  3. 3. Erosion is……. the wearing away of materials by one of four processes:  Corrosion = chemical reactions of salt water weakening rocks like an acid  Attrition = Pebbles hitting into each other or into cliffs making rocks break and get smaller and rounder  Abrasion = ‘sand paper’ effect. Waves throwing small stones and pebbles at cliffs and beaches to smooth the material  Hydraulic Action = Power of the water forcing its way into cracks and weaknesses in rocks, splitting apart
  4. 4. Recap : landforms
  5. 5. The main landforms created by erosion are…
  6. 6. Headlands and Bays
  7. 7. Wave cut notches and platforms
  8. 8. Wave-cut platform – Burgh Island, Devon Wave cut platform Southerndown, South Wales.
  9. 9. Beaches develop where the supply of sediment exceeds loss through backwash and longshore drift. Beaches are usually distinguished as either … Shingle or Sand Shingle beaches are free draining so there is little backwash of material to sea. As a consequence, they are usually steeper.
  10. 10. How was this landform created?
  11. 11. Spits and Bars Where there is a change in the coastline e.g. a headland or an estuary mouth, longshore drift may continue to deposit sediments into the sea forming a spit.
  12. 12. Local currents and changes in wind direction may curve the end of the spit landwards creating a hooked tip. The presence of the estuary discharging river water into the sea prevents the spit from developing into a bar. Such a feature is known as a recurved spit wind
  13. 13. Exam Q • How does geology influence the speed of erosion at the coast? [2marks]
  14. 14. The geology of the coast affects how much it is eroded. More resistant rocks (e.g. chalk) erode more slowly than less resistant rocks (e.g. clay, limestone) This gives us BAYS And HEADLANDS
  15. 15. The Jurassic Coast • The Jurassic Coast is a section of coastline in Southern England that shows geology over millions of years. • The coastline first began forming 250million years ago • Dorset shows the geology of the Jurassic period, between 200-140million years ago
  16. 16. What about waves?
  17. 17. If you were a wave, and you wanted to grow big and strong so you could knock the UK’s block off, which direction would you come from? Why?
  18. 18. Waves • There are two main types of waves: • Constructive vs Destructive
  19. 19. Exam Q Describe and explain how constructive and destructive waves work. Use keywords or examples where possible. [4marks]
  20. 20. How do waves influence landforms? Longshore drift
  21. 21. Longshore drift…
  22. 22. Long-shore drift (LSD)
  23. 23. Exam Q: “With the use of a diagram, explain the process and effects of longshore drift, and how it can be managed” [6marks]
  24. 24. Reminder about Grid References
  25. 25. Constructive or Destructive coastline? What evidence from the map?