Paper 2: Uk's Evolving Physical Landscape Flashcards
Where is Malham cove located and what was it?
Yorkshire Pennines, north of England. It was once a huge water fall, 80m high.
Why does Malham cove form a mystery for geologists?
The rock it is made from co sissy of limestone but it contains crushed shells of coral that lived in the sea 300 million years ago.
What 3 factors form Malham cove today?
- Geology
- Past tectonic activity
- passed processes caused by glaciation
His did geology affect the formation of Malham cove today?
300 million years ago the UK was covered by tropical sea where tropical sea and coral thrived. As they died they fell to the ocean bed forming a horizontal layer called strata. Two processes then turned them into rock:
- as more skeletons fell they crushed those beneath them, eventually squeezing the water out and compacting it into rock.
- calcium carbonate (occurs naturally in sea water) crystallised around the fragments this cemented them together and persevered fossils.
How do geologists now the age of the fossils in Malham Cove?
Using Carbon dating. This means they now the fossils lived in the Carboniferous period.
Why does the rocks in Malham cove vary in resistance?
Other rock strata was deposited on top of the limestone. It consists of more resistant rock, e.g millstone grit. It resists erosion and forms the highest peaks in the Pennines and protects weaker sands and snakes beneath.
What is carbon dating?
Using radioactive testing to find the age of rocks, which contained living materials.
What is erosion?
The wearing away of a landscape.
What sort of rocks does upland UK consist of?
They consist of more resistant rock, such as metamorphic and igneous rock and some sandstone.
What sort of rocks does lowland areas of the UK consist of?
Younger, less resistant sedimentary rock.
How did past tectonic processes affect how Malham cove looks today?
- the plates on which the UK sits shifted away from the tropics.
- convention currents from beneath the sea uplifted rocks that became land.
- During uplift some of the rocks snapped and moved along faults in a series of earthquakes over thousands of years. Each movement disturbed the strata so that they tilted. Sometimes, the the faults form a steep edge where uplift had raised some parts more than others.
How did past glaciation processes affect how Malham cove looks today?
As the Pennines were uplifted, rivers life the wharf eroded into them creating v-shaped valleys. But he most recent ice age brought glaciers.
They had 2 affects:
-They altered river valleys making them u-shaped valleys (made them deeper and wider)
-as the glaciers meltted they left features like these.
Give two points that prove Britain’s geology is of value:
- Cornwall has large amounts of tin and copper which made the county wealthy.
- Huge strata of coal helped to make Britain the world first industrial nation other resources include building stone (marble) and raw materials (iron core).
What are igneous rocks?
Earths oldest rock, formed from lavas and deep magmas that have cooled and crystallised. They have interlocking crystals and the crystal size depends on how long the magma takes to cool. This rock is usually resistant to erosion.
What are sediments rocks?
Formed from sediments eroded and deposited by rivers or the sea on the sea bed. Some are resistant (sandstone) while others crumble easily. Can contain fossils and have round porous grains. Rock is permeable.
What is metamorphic rock?
These are sedimentary rocks that are heated and then compressed, they form under extreme pressure and temperatures. They are resistant and have arranged crystals.
North West of of the England the rocks are?
Older
More resistant such as igneous and metamorphic
More faults where upload areas were uplifted by tectonic activity
It is the opposite in the southeast.
Examples of igneous rock?
Basalt
Granite -formed underground large crystals.
Both are resistant.
Examples of sediments rock?
Sandstone Limestone Chalk - medium slightly porous Millstone grit - very resistant clay - soft and crumbly generally weak.
Vary in resistance
Example of metamorphic rock?
Slate
Schist
Marble
all very resistant
What is scree?
Rock fragments these make the ground ruff. The are often found in places like the Lake District.
What does scree consist of?
Angular rock pieces created by freeze thaw weathering .
How does freeze thaw weathering occur?
In the winter temperatures are often below freezing in the night but warmer during the day. Rainwater gets into cracks in the rocks freezes and expands by 10%. Expansion widens the crack and eventually the rock breaks into pieces. This forms scree.
How do slope processes affect the country side?
- scree fragments are unstable and move easily during rockfalls, increasing dangers for walkers.
- Landslides are common. The Lake District is the UK’s wettest region (Over 2000mm of rain a year) Rain adds to the weight of weathered rocks so it slides easily.
What is weathering?
The physical, chemical or biological breakdown of solid rock by the action of weather or plants.
Where is the Weald located?
Southern England, Kent, Sussex. This area consists of undulating (gently rolling hills) it is lower than the Lake District.
How has the Weald’s landscape been affected?
By geology. The Weald was once a dome of folded rocks, forming an arch called the anticline. The strata used to be continuous but, linking what is now known as the south and north downs. However erosion has left alternate strata and less resistant rock to form a landscape known as scarp and vale topography.
What is the landscape of the Weald like currently?
-resistant rocks, like chalk, form escarpments.
-behind the escarpment, gently slopes follow the angle at which the rocks were tilted.
_softer clays are lower and flatter, forming the vales.
What different types of weathering occur in the Lake District and the Weald and why?
Different types of weathering occur because of the different weather.
Chalk(calcium carbonate) is an alkali so is affected by rain/acid rain.
Tree and shrub roots break up solid rock.
What are the three different types of weathering? Give examples.
Physical weathering - freeze thaw, onion skin
Chemical - rain (naturally, slightly acidic), acid rain
Biological - roots breaking through rocks and animals.
Why is it unusual to find chalk near water sources?
Because it is porous. (Not wet unless saturated after weather).
Why are rivers common in vales?
Because clay is impermeable.
Why is clay impermeable?
During and after the last ice age, water in the clay froze, making it impermeable. Then fresh water formed rivers and valleys. As the climate warmed, water speeded the clay once again leaving dry valley where rivers had once flowed.
What is soil creep?
This is a slope process and is a very slow process. This is caused when rain dislodged particles of soil causing it to slowly creep down the slope. In general slope processes are slower in the Lake District.
What did the Norse Farmers in the Yorkshire Dales use to build?
They used limestone as it was strong. They also used the boulders and rocks left by rivers or melting glaciers in the valley bottom. They used these to also build dry stone walls as field boundaries.
What were the Norse farmers in the Yorkshire Dales influenced by and what did they do to adapt?
Influenced by the Pennine climate.
-cold winters and short growing season meant sheep farming was best. In winter sheep were kept at the bottom of valley fields.in summer they grazed upland. Fields in valley bottom produced hay for winter.
-winter hay stored in stone barns. Farmers tended to love near their animals due to convenience. They built long houses consisting of a house and a barn together so animals could be kept inside during bad weather. This led to a disperse pattern of isolated farms.
Where is East Anglia located and how is it different to the Pennines?
Located in Eastern England and is low lying unlike Pennines. Flat and less than 100 meters above sea level. It’s coastline faves Europe.
What is East Anglia’s geology? And how is this used for benefit?
Mainly sands, clays known as till, which were deposited by glaciers from the last ice age. Till produced fertile soil for Arable crop farming, hedges are used for field boundaries instead if stone walls. Below the surface the geology is chalk. Chalk is too crumbly for building.
What is scree?
Rock fragments these make the ground ruff. The are often found in places like the Lake District.
What does scree consist of?
Angular rock pieces created by freeze thaw weathering .
How does freeze thaw weathering occur?
In the winter temperatures are often below freezing in the night but warmer during the day. Rainwater gets into cracks in the rocks freezes and expands by 10%. Expansion widens the crack and eventually the rock breaks into pieces. This forms scree.
How do slope processes affect the country side?
- scree fragments are unstable and move easily during rockfalls, increasing dangers for walkers.
- Landslides are common. The Lake District is the UK’s wettest region (Over 2000mm of rain a year) Rain adds to the weight of weathered rocks so it slides easily.
What is weathering?
The physical, chemical or biological breakdown of solid rock by the action of weather or plants.
Where is the Weald located?
Southern England, Kent, Sussex. This area consists of undulating (gently rolling hills) it is lower than the Lake District.
How has the Weald’s landscape been affected?
By geology. The Weald was once a dome of folded rocks, forming an arch called the anticline. The strata used to be continuous but, linking what is now known as the south and north downs. However erosion has left alternate strata and less resistant rock to form a landscape known as scarp and vale topography.
What is the landscape of the Weald like currently?
-resistant rocks, like chalk, form escarpments.
-behind the escarpment, gently slopes follow the angle at which the rocks were tilted.
_softer clays are lower and flatter, forming the vales.
What different types of weathering occur in the Lake District and the Weald and why?
Different types of weathering occur because of the different weather.
Chalk(calcium carbonate) is an alkali so is affected by rain/acid rain.
Tree and shrub roots break up solid rock.
What are the three different types of weathering? Give examples.
Physical weathering - freeze thaw, onion skin
Chemical - rain (naturally, slightly acidic), acid rain
Biological - roots breaking through rocks and animals.
