High energy coastline

• How long is the stretch of coastline and what is it like? (Saltburn to Flamborough Head)

  • 60km
  • Rocky, upland area
• What is the geology like at North York Moors?

  • Sandstones, shales and limestones formed in Jurassic period and carboniferous rock
• What is the geology like at Flamborough Head?

  • Large chalk headland
  • Cliffs topped with till
• What is the most dominant wave direction?

  North and Northeast
• How far is the fetch distance?

  1500km
• Where is the wave energy highest and why?

  • Coast that's north-facing e.g area nearest to Saltburn as that's where most exposed parts of the coast are
• Why do rates of erosion vary?

  • Differences in wave energy inputs
  • Variations in resistance of the different geologies
• What is the shale and clay erosion rate?

  • 0.8m/yr
• WHat is the sandstone and limestone erosion rate?

  Less than 0.1m/yr
• What is the wave height?

  In 2010/11, it exceeded 4m during summer
• What process operates from North to South?

  Longshore drift
• What is the sediment cell and sub-cell number?

  1 and 1d
• From St Abbs, Scotland to Flamborough, why has sediment come from sub cell 1d (offshore)?

  Its been driven onshore as sea levels rose at the end of last glacial period
• How do cliffs supply sediment?

  • Cliff erosion supplies sandstone and chalk from resistant rock outcrops
  • Boulder clay deposits yield significant amounts of gravel
• What is sediment from rivers like?

  Supplies limited amounts of sediment due to construction of weirs and reinforced banks
• What was the net increase in beach sediment 2008-11 at Saltburn?

  9245m$^2$
• What are the details of sediment at Filey Bay

  • Zones of beach erosion and accretion were observed which reflect influence of winter storm systems
  • Erosion at back of beach significant in winter of 2010-11
• Where is erosion mostly occuring?

  In the North, near Sunderland and Teeside
• WHat direction is nearshore sediment moving in?

  Mostly in the South
• Where is sediment input occuring?

  By Whitby and Scarborough
• What are cliffs like along the stretch of coastline?

  • Cliff profiles have vertical face
  • Overlain by a layer of weak glacial till which has a much lower angle
• What are the cliffs like at Flamborough?

  • Made of chalk so physically strong with tightly bonded mineral particles
  • Vertical cliffs 20-30m high with overlying till lowered by mass movement processes to an angle of 40$^{\circ}$
• What are the cliffs like between Saltburn and Robin Hood Bay?

  • Much higher but with stepped profile, reflecting more varied geology
  • Steeper slope segments are formed in more resistant sandstones and limestones
  • Gentler slopes correlates to weaker clays and shales, lowered by mass movement processes
• Give details of shore platforms at Robin Hood's Bay

  • It's eroded into lower lias shales
  • Platform slopes at typical angle of 1 degree, though ramped sections are as steep as 15 degrees
  • Minimum width of 500m, but extends much further into offshore zone
  • Formed within last 6000 years, during times of predominantly stable sea levels
• Describe Robin Hood's Bay

  • Eroded into weak shales with more resistant bands of sandstone either side forming headlands of Ravenscar to the South and Ness point to the North
• Describe Filey Bay

  Developed further south in weak kimmeridge clay and flanked by more resistant limestone and chalk
• Describe Flamborough

  Most dominant headland formed of chalk, with deep bays either side formed of clay
• What features are found in Selwick's Bay at Flamborough Head?

  Caves, arches and Green Stacks Pinnacles - isolated at end of headland following collapse of an arch roof.
• Give details on stacks, geos and blowholes

  • Over 50 geos formed along coastline, most aligned to NE/NNE, facing dominant wave direction
  • Blowholes developed where vertical master joints in chalk have been enlarged
• Why are there funnel shaped depressions on the cliff tops?

  Chalk and boulder clay collapsed into underlying sea caves
• Where are beaches found?

  In sheltered low energy environments eg Scarborough and Filey Bay
• Why do sediments accumulate slowly?

  • Due to low inputs of sediment from river and slow rates of erosion at the resistant rocks
  • High energy waves remove sediment before it can accumulate
• Why does this stretch of coastline lack splits despite longshore drift operating?

  • Due partly to the high tidal range of 4m
  • Lack of estaurine environments that would provide sediment sinks