Rivers And Coasts Flashcards
(22 cards)
What are the 4 types of erosions?
- Hydraulic action
- Abrasion
- Attrition
- Solution
What are the 4 types of transportation?
- Traction
- Saltation
- Suspension
- Solution
What is hydraulic action?
The force of the waves breaking the cliff face down
What is abrasion?
Rocks hit against the cliff face breaking down the coast
What is attrition?
The rocks hit against each other breaking down
What is solution (erosion)?
The rocks are dissolved by the acidic sea
What is traction?
Sediment is too large to be carried and so is rolled along the sea floor
What is saltation?
Sediment is still large and it is carried over short hops before being re-deposited
What is suspension?
Sediment carried by the sea
What is solution (transport)?
Sediment is dissolved by the sea and carried
When were the boscastle floods?
16th August 2004 in Northern Cornwall
Why did the Bostcastle floods happen?
- there was heavy rainfall
- deforestation
- it was located between 2 tributaries
- ground was impermeable
- village was in a valley
How many homes destroyed in the Boscatle floods?
5 homes destroyed and 80 cars washed in to the mouth of the river
How many deaths in the Boscastle floods?
No deaths but 1 broken thumb
How many people rescued from the boscastle floods?
150 people rescued by 7 helicopters
What were the economic effects of the boscastle floods?
- insurance increased
- loss of money for business as they had to shut for 3 months
- loss of income as tourism decreased
What were the environmental effects of the boscastle floods?
- loss of habitat
- tree uprooted
- oil spills in the sea from cars floating there
What were the short term responses of the boscastle floods?
- search and rescue
- emergency shelters set up mainly for tourists to stay in
- food and blankets donated
What were the long term responses for the boscastle floods?
- £4.5 million spent on dredging of the river, raising the car park and improving drainage and sewage in the area
- bridges raised so trees no longer get trapped under them
What are the two types of waves?
- destructive waves
- constructive waves
What are the characteristics of a destructive wave?
- strong backwash
- weak swash
- tall waves that are close together
What are the characteristics of a constructive wave?
- weak backwash
- strong swash
- small long waves
