Coastal Landscapes

High Energy Coast Case Study: Saltburn to Flamborough Head

Introduction

The coastline between Saltburn and Flamborough Head on the North Yorkshire coast of England is a classic example of a high-energy coastline. This 60km stretch is characterised by resistant rock formations, dramatic cliffs, headlands, bays, and active geomorphological processes.

1. Physical Factors Influencing Landform Formation

  • Geology:
    • The coastline consists of discordant geology:
      • Hard rock: Chalk (Flamborough Head) and sandstone (Saltburn) form resistant features like headlands and cliffs.
      • Soft rock: Clay and shale erode faster, forming bays (e.g., Filey Bay).
    • Geological structures, such as faults, bedding planes, and joints, influence the location of features like caves, arches, and stacks.
  • Wave Energy:
    • This is a high-energy coastline due to strong wave activity driven by prevailing north and northeast winds and a large fetch from the North Sea.
    • Destructive waves dominate, leading to rapid erosion of soft rocks and significant cliff retreat.
  • Tidal Range and Currents:
    • A large tidal range (over 4m) exposes wave-cut platforms and increases the zone of wave attack.
    • Strong currents and storm surges exacerbate erosion and transport sediment along the coast.
  • Climate and Weather:
    • Frequent storms and high rainfall enhance weathering and mass movement, particularly on the softer rocks.
    • Freeze-thaw weathering is prominent in winter, weakening cliff faces.

2. Inter-relationship of Landforms within the Landscape System

The Saltburn to Flamborough Head coastline demonstrates a dynamic interplay of erosional and depositional landforms:

  • Headlands and Bays:
    • At Flamborough Head, resistant chalk forms a prominent headland, while softer clays create bays like Filey Bay.
    • Wave refraction focuses energy on headlands, causing erosion and features like cliffs, caves, arches, and stacks.
  • Cliffs and Wave-Cut Platforms:
    • High cliffs, such as those at Flamborough (20-30m tall), are eroded at their base to form wave-cut notches. Repeated cliff collapse leaves behind wave-cut platforms.
    • These platforms, such as those near Robin Hood’s Bay, extend seawards as cliffs retreat.
  • Caves, Arches, Stacks, and Stumps:
    • Weaknesses in the chalk cliffs at Flamborough are exploited by hydraulic action and abrasion, forming caves.
    • Continued erosion creates arches (e.g., Selwicks Bay) and later stacks and stumps, such as the well-known stack Old Harry.
  • Beaches:
    • Sediment eroded from cliffs and transported via longshore drift accumulates in sheltered areas, forming beaches like those near Saltburn.
    • Beaches are narrow due to the dominance of destructive waves.
  • Spits:
    • Sediment transport southwards contributes to the development of depositional features like Filey Spit, demonstrating the link between erosion at headlands and deposition further along the coast.

3. Landscape Changes Over Time

The landscape system changes over different timeframes, from seconds to millennia:

  • Cliff Collapse (Seconds):
    • Sudden mass movement events, such as rockfalls or landslides, occur due to undercutting by waves or saturation from heavy rainfall.
    • These events contribute to rapid changes in cliff profiles.
  • Seasonal Beach Profile Changes (Months):
    • During winter, destructive waves erode beaches, creating steep profiles and removing sediment to offshore bars.
    • In summer, constructive waves return sediment, rebuilding the beach and creating gentler profiles.
  • Spit Growth (Millennia):
    • Longshore drift transports sediment southwards, gradually extending depositional features like spits and onshore bars. Over thousands of years, these features evolve to form lagoons or salt marshes.
  • Geological Time (Millennia to Millions of Years):
    • The landscape has been shaped by glacial and interglacial periods, which influenced sea levels and sediment supply.
    • Rising sea levels following the last Ice Age (Holocene) submerged parts of the coastline, creating the current headland and bay features.

Summary of Key Processes

  • Erosion: Hydraulic action, abrasion, attrition, and solution dominate, particularly on headlands and cliffs.
  • Weathering: Freeze-thaw and biological weathering weaken rocks, aiding cliff retreat.
  • Transportation: Longshore drift moves sediment along the coastline.
  • Deposition: Occurs in low-energy zones, creating beaches and spits.
  • Mass Movement: Rockfalls and landslides contribute to the rapid retreat of cliffs.

Conclusion

The Saltburn to Flamborough Head coastline illustrates the dynamic nature of high-energy coastal systems. Interacting physical factors create a diverse range of erosional and depositional landforms that are constantly evolving. From rapid cliff collapses to the slow growth of spits, this coastline exemplifies how geomorphological processes operate across a variety of timescales.