Aim: To understand how weathering and mass movement processes occur along the coast

Quick Recap

• Can you remember from last lesson what the following words mean?

• Fetch• Beach• Crest• Swash• Backwash• Constructive• Destructive

A clue!

………………………………………. wave

………………………………………. wave

A) Processes of Weathering

• These are _____________ that break down rocks in one place which involves no ____________ . It differs to erosion, as erosion needs movement to ______ .

A. Processes, water, explodeB. Processes, movement, work C. Animals, movement, ignite. D. People, machines, erupt

1) Physical / Freeze Thaw

• Freeze thaw weathering

• This is the most common.• It involves the alternative actions of freezing

and melting.• It only occurs in places where there the

temperature fluctuates around 0 degrees.

2) Chemical Weathering

• This is also known as solution. Like sugar dissolves in tea, some rocks (e.g. Limestone) and minerals dissolve in rainwater.

2) Chemical Weathering

• The traces of acid in rainwater (water + carbon dioxide = weak carbonic acid) form a chemical reaction between the acid and limestone.

• This can form ‘limestone pavements’.

2) Chemical weathering

• Florida Sink hole info here and video here

3) Biological Weathering

• Plant and animals may weaken rock structure. E.g. sand martins along the Norfolk coastline.

B. Processes of Mass Movement

• Rock fall - here• Landslide • Mudflow• Slump – rotational slip

• Using the worksheet, complete the four diagrams to show these processes using your text book p147

Sketch and annotate this image to show mass movement

Homework

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