5 Saltburn to Flamborough Head - High energy

Question 1

General information on Saltburn to Flamborough Head

Answer 1

Rocky, upland area
60km long coastal environment
Costal landforms reflected by high energy waves
Sediment cell 1

Question 2

Describe the geology of the North York Moors

Answer 2

• North York Moors rise up to 400m above sea level and comprise mainly Jurassic sandstones, shales and limestones and some carboniferous rocks

Question 3

What are the main 2 areas of prominent geology?

Answer 3

North York Moors
Flamborough Head

Question 4

Describe the geology of Flamborough Head

Answer 4

Chalk Headland with rocks dating from the late Cretaceous
Topped by till - a weak glacial deposit left behind by the glaciers of the Devensian glacial period

Question 5

Energy: Describe the waves in the coastal environment

Answer 5

Dominant waves from the North and Northwest
Fetch of over 1500km

Question 6

Energy: What is the most exposed area of the environment?

Answer 6

North-facing coasts (eg area nearest Saltburn)
Receive highest inputs of wave energy

Question 7

Energy/Processes: Why do the rates of erosion vary?

Answer 7

Differences in wave energy inputs and variations in the resistance of the different geologies
Areas of weak shale and clay experience erosion rates of 0.8m/ year averagely
More resistant sandstones and limestones only erode at rates of less than 0.1m/year

Question 8

Energy: What is the wave height in Whitby Bay?

Answer 8

Monitoring using floating buoys revealed wave height often exceeds 4m, even in summer months

Question 9

Energy/Processes: What other significant process is occurring?

Answer 9

High-energy inputs cause significant longshore drift from north to south along the coastline
In places, this sediment movement is interrupted by headlands, and sand and shingle then accumulate to form beaches in the bays, such as in Filey Bay

Question 10

Sediment: What are the main sediment sources?

Answer 10

• Cliff erosion - sandstone and chalk from resistant chalk outcrops and weaker boulder clay deposits yield significant volumes of gravel
• Seafloor sediments driven onshore by rising sea level during the Flandrian Transgression

Question 11

Sediment: Why does the only large river, The Esk, not provide lots of sediment?

Answer 11

The Esk enters the North Sea at Whitby
Supply is limited due to the constructions of weirs and reinforced banks along its course

Question 12

Sediment: Is there an increase or decrease of beach sediment at Saltburn?

Answer 12

Increase
9245m3 from 2008-2011
Beach erosion and accretion at Filey Bay - influence of winter storm systems with erosion at the back of the beach being particularly significant in the winter of 2010-11

Question 13

Sediment: Why are there few spits?

Answer 13

Despite LSD, few spits due to high tidal range (increased energy input so less deposition) and few estuaries which would naturally act as sediment sinks

Question 14

Sediment: Why are there few well-developed beaches?

Answer 14

Low sediment input - few rivers, little erosion of resistant rocks, high wave energy and active LSD
Beaches found (Scarborough, Filey Bay) due to local sheltered, low energy environments

Question 15

Erosional landforms: Describe the nature of Flamborough Head

Answer 15

• Chalk - strong physical lithology with tightly-bonded minerals
• Produces vertical cliffs 20-30m high
• Overlying stratum of glacial till lowered by mass movement to an angle of 40’
• Joints, faults and other lines of weakness are exploited by waves, creating caves, arches and stacks (Green Stacks Pinnacle) at Selwick’s Bay
• Over 50 gets, aligned NE or NNE (facing dominant waves)
• Multiple blowholes forming where vertical joints have been enlarged, causing the collapse of the overlying chalk and till to create funnel-shaped depressions in the headland

Question 16

Erosional landforms: What are the cliffs like between Robin Hood’s Bay and Saltburn?

Answer 16

Higher and steeped profile
Reflects varied geology - steep segments on more resistant sandstone and limestone, gentler slopes on weaker clays and shales (more prone to mass movement)

Question 17

Erosional landforms: What are the shore platforms like in the coastal environment?

Answer 17

• Left behind by the retreating cliffs
• At Robin Hood’s Bay - Lower Lias Shale has typical slope of 1’ (small ramped sections reach 15’)
• Platform has maximum width of 500m, but extends further into the offshore zone - likely formed by erosive processes during the last 6000 years (current period of sea level stability), although some believe they are relict feature formed during earlier interglacials

Question 18

Erosional landforms: Why are cliffs tend to have a vertical profile?

Answer 18

Sedimentary rocks are horizontally bedded

Question 19

Erosional landforms: What has discordant rock strata lead to?

Answer 19

Headland and bays
- Robin Hood’s Bay, the bay has been eroded from relative weak shales, with the headlands (Ness Point to the north and Ravenscar to the south) are formed of more resistant sandstone
- Filey Bay, weak Kimmeridge clay is flanked by headlands of resistant chalk and limestone