Answer the following exam question (you have 5mins) Describe and explain the physical processes that can affect rocks? (6 marks)
Example answers Level 1 answer - Mentioned that there are two types of physical weathering, freeze-thaw and onion skin. No detail, just a list. Level 2 answer - Begun to describe and explain the actual processes that take place. Freeze-thaw = cold conditions around 0 degrees. Onion skin = very hot conditions. Brief mention of processes. Level 3 answer - Detailed answer containing geographical vocab. Answer written in clear steps with the help of diagrams. Talks about two types of physical weathering, describes freeze-thaw (3 steps) and then onion skin (3 clear steps)
To be able to describe the characteristics of granite scenery
2) To be able to describe the formation of granite landscapes
Where are granite rocks in the UK found? Granite rocks in the UK are found to the north and west of the Tees-Exe line. Igneous outcrops in red and dark-pink In SW England, granite gives flat topped moorland plateaus with many rock outcrops, sometimes forming rock blocks called ‘Tors’ In Scotland there are the granite peaks of the Grampians. They are rocky and frost shattered. Where land is flat it is wet and boggy.
How are granite rocks formed? - Granite is an igneous rock, normally found deep in the earth's crust and made of crystals formed from the cooling of molten magma. - It is sometimes exposed at the surface (extrusive) where the sedimentary rock, such as sandstone, has been eroded away. - However, it can be formed by magma cooling underground after being intruded into other rocks before reaching the surface.
What is the drainage like in granite areas?
Granite is a hard, igneous rock.
It is an impermeable rock that produces a landscape of high ground, and wet, waterlogged areas.
Outcrops of granite like this one can be seen throughout Dartmoor, in southwest England, and particularly on hilltops, where tors have been formed.
There are two main features found in granite landscapes:-
Batholith: A very large body of intrusive igneous rock, usually granite, that has been exposed by erosion of the overlying rock Tor: A large outcrop of granite, usually seen as a number of round boulders
What is a ‘tor’ and how are they formed?
- A tor is the rock which remains after the rocks around it have been weathered
Granite can be eroded by freeze-thaw weathering and by chemical erosion
The granite is broken down most effectively where there are more joints or cracks in the rock, and it is most resistant where there are fewer joints
The unweathered rock forms a tor, an upstanding, isolated mass of rock, like this one on Dartmoor
Economic uses Land uses Granite used for building (it’s a very hard rock and lasts for a long time) Also used for headstones in cemetaries Granite + chemical weathering = china clay China clay used for pottery, and as an ingredient in toothpaste, paper, paint, and face creme Uplands: Very wet, marshy, bogs Acidic infertile soils Used for grazing sheep, horses Lowlands: used for pasture land for grazing cows Often find woodland More fertile land