Headlands and Erosional Processes

Question 1

how are headlands formed and by what processes

Answer 1

• hydraulic action
• the cliff face consists of alternating hard and soft rock
• soft rock is eroded more than hard rock
• so overtime pockets of more eroded soft rocks are formed

Question 2

what are the four types of erosion

Answer 2

• hydraulic action
• abrasion
• attrition
• solution

Question 3

what is hydraulic action

Answer 3

• when the force of the waves crashing against the cliff face squeezes air in cracks
• which forces rocks open overtime

Question 4

what is abration

Answer 4

• bits of soft rock and sand grind down cliff face like sandpaper
• rocks thrown at cliffs chip them overtime

Question 5

what is attrition

Answer 5

• waves smashing rocks and pebbles into each other

- breaking them and making them smaller

Question 6

what is solution

Answer 6

• breakdown of rock by chemical action by weak acid attacking rocks
• chemical reaction between acid in water and rocks

Question 7

what are the four structures found in headlands

Answer 7

• CASS
• caves
• arches
• stacks
• stumps

Question 8

what is the complete process of headland erosion

Answer 8

• hydraulic action causes large cracks to from on the cliff face
• cracks grow into a notch then cave as destructive abrasive waves erode
• large cave causes wave refraction, drawing water to the cave in all directions
• makes a back-to-back cave on both sides
• sea breaks through making an arch
• the base is widened by wave cut notches
• top of arch eventually collapses
• leaving a pillar of detached rock (stack)
• notches form at the base of stack making it unstable
• stack topples into the sea leaving a stump

Question 9

what are the characteristics of a wave

Answer 9

• several meters high
• widest part is entrance
• taper back a long way

Question 10

what are the characteristics of an arch

Answer 10

• unsupported top of arch
• wave cut notches at base
• water flows through gap

Question 11

what are the characteristics of a stack

Answer 11

• detached blocks of pillars
• wave cut notches at the base
• several meters high
• hard rock

Question 12

what are the characteristics of a stump

Answer 12

• bases of a collapsed stack
• only seen at low tides
• usually submerged

Question 13

what is deposition

Answer 13

when material carried by the sea is dropped on the coast

Question 14

what are the factors that affect the amount of deposition

Answer 14

• wind
• transportation
• erosion (strong swash and backwash)