Coasts

Question 1

What are the two main Sub-Aerial Weathering processes? What do they do to the coast?

Answer 1

Weathering and mass movement. Alters shape of coastline. On cliff face to weaken it and provide coastal erosion.

Question 2

What is the meaning and give examples of weathering?

Answer 2

Mechanical or physical weathering is the fracture and breakdown of rocks into fragments. Along the coast, it may be caused by frost shattering (freeze-thaw), salt crystallisation, wetting and drying, or even biologically.

Question 3

Biological Weathering

Answer 3

Plant Roots expanding rocks and breaking down cliffs.

Question 4

Chemical Weathering

Answer 4

Weak chemical reactions of rocks. Eg water with limestone. Acid rain caused by rainwater mixed with carbon dioxide in air, forms carbonic acid.

Question 5

Give example of a Mass Movement

Answer 5

Land slide- large amount of land falling at once- retains structure until it hits the floor and them breaks up.

Question 6

Mud Flows

Answer 6

A mudflow is an earthflow consisting of material that is wet enough to flow rapidly and that contains at least 50 percent sand, silt, and clay-sized particles

Question 7

Slump

Answer 7

Rainwater infiltrates the cliff through porous material.
Creates a slip plane.
The weight of the saturated clay causes the material to slump.

Question 8

Isostatic Sea Level Change

Answer 8

Smaller than Eustatic. Land Buoyancy. End of ice age, weight of ice removed, land will start to rise causing relative sea levels to fall. Slower than Eustatic.

Question 9

Eustatic Sea Level Change

Answer 9

Variations of sea level due to inputs and outputs eg glacial.. Increasing sea levels. Freshwater sheets.