Do now!

Can you continue the questions on pages 84 and

85?

Last lesson

• Chemical and physical weathering

Chemical weatheringRain is slightly acidic as it contains substances dissolved from the air. It can react with rock, dissolving it.

Chemical weathering

Some rocks are dissolved more by acid rain than others

Limestone “pavement”

Physical weathering

Rocks can be weathered by physical changes

Physical weathering

When rocks are hot they expand, and when they cool they contract. Repeated changes cause the rock to crack, often causing rock to peel off.

Sometimes called “onion-skin weathering”

Physical weathering

Freeze-thaw weathering is another example

You now know all about freeze-thaw weathering

Today’s lesson

• Transport of weathered rock

• Soil

• Rock cycle

Transport

Transport

Rock falls to the bottom of rock faces and may be transported away by fast moving streams.

Abrasion

The rocks in the stream bed rub against each other and wear away. This is abrasion.

Sediment

The bits of rock in the stream bed are called sediment.

Deposit

Smaller rock fragments are carried further than large ones, eventually being deposited on the bottom in slow water.

Let’s try some questions!

Stick the sheet in and fill in the gaps.

You have 8 minutes!

What is soil?

What is soil?

A mixture of stones, smaller rock particles (sand) and humus (remains of dead plants and animals)

Copy?!

Can you copy the table on page 91?

The Rock Cycle

Can you read page 100 very carefully?

The Rock Cycle

Can you copy the diagram on page 100?