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Hello, geographers.

My name's Mrs. Homingo, and I'm looking forward to teaching you today.

I hope you're going to enjoy the lesson and learn lots.

Let's get started.

Today's lesson looks at the varied geology of the UK, and by the end of the lesson, you'll be able to describe the characteristics and the distribution of rock types in the UK.

There are five key words for today's lesson.

Igneous rocks, rocks formed from the cooling of molten magma.

Sedimentary rocks, rocks formed from accumulated sediments.

Metamorphic rocks, rocks changed by heat and or pressure, and chalk, a soft white sedimentary rock found in southern England, and granite, a hard igneous rock found in upland UK areas.

There two learning cycles for today's lesson.

The first is the UK's main rock types and their characteristics.

The second is the distribution of the UK's main rock types.

Let's get started with our first and have a look at the main rock types found in the UK and consider their characteristics.

The UK that's made up of a variety of rock types, each formed in different ways over millions of years.

And we can see here looking at this geology map, the different colours represent the different types of rocks.

We can see that across the UK, there are many different colours on that map.

Izzy says, "Did you know that the rocks beneath your feet could be up to 3 billion years old and completely different from those in another part of the UK?" So there are three main types of rock in the UK.

Igneous rocks, sedimentary rocks, and metamorphic rocks.

And this map here shows us the distribution of these three different types of rocks.

Each type has its own distinctive physical and chemical characteristics, and their distribution in the UK is also distinctive.

Looking at that map, we can see that igneous and metamorphic rocks tend to be in the northwest of the UK and sedimentary rocks are in central and southern areas.

Igneous rocks are linked to volcanic activity and they form when magma or lava cools and hardens and forms crystals.

Lava cools on the surface and this happens quickly forming small crystals and we call this extrusive igneous rock.

Magma cools underground and it cools more slowly and it forms large crystals, which we call intrusive igneous rock.

Now let's consider the main characteristics of igneous rock.

So it's made, as we've said, from interlocking crystals that vary in size depending on the type of rock.

They're usually very hard and resistant to erosion.

There are no fossils due to the extreme temperatures found in the molten rock from which it forms. It can be intrusive, which form large crystals, or extrusive, which which form small crystals, and usually it's impermeable.

Quick check for you now.

Which of these are common characteristics of igneous rock? Impermeable, easily eroded, or made of interlocking crystals.

Pause the video and come back when you've had a go.

I hope you correctly identified impermeable and made of interlocking crystals as the common characteristics of igneous rock.

Igneous rock is in fact hard and resistant to erosion, so B is definitely not correct.

Sedimentary rock is made from layers of sediment, sand, mud, and dead plants and animals.

Over time, these layers are compressed and compacted to form rock.

Examples that we have include limestone, which are formed from marine shells, coral, and other sea creature remains that build up over time under the sea and are compressed and compacted to form rock.

And chalk, which is a type of limestone which is formed from microscopic plankton.

And finally, sandstone formed from sand particles.

Let's look at the main characteristics of sedimentary rocks.

They're layered and usually softer than igneous rocks, and that's because the sediment is laid down in layers and then compacted and compressed to form the rock.

Often more easily eroded.

They may contain fossils as they're made from organic material.

Often underlies lowland areas in the UK and they're often permeable.

A quick check for you now.

What type of rock is this and how does it form? Pause the video and come back when you've had a go answering this question.

I hope you said it was sedimentary rock.

And sedimentary rock is made from layers of sediment, sand, mud, and dead plants and animals.

The layers are then compressed and compacted over time to form rock.

For example, chalk.

Let's have a look now at metamorphic rocks.

They are formed when existing rocks are changed by heat from the mantle and the core and pressure from the weight of overlying rocks.

But this happens without melting.

Examples include slate formed from shale, and this is found in North Wales, and marble made from limestone, which is found in the Scottish Highlands.

So have a look at the characteristics of metamorphic rocks.

They have a crystalline structure or layers, which is known as foliation.

They're usually very hard and resistant to erosion.

They do not contain fossils due to the high temperatures and pressure during metamorphism, so the change, and they're often found in upland mountainous areas.

That's because they are resistant to erosion.

They're usually impermeable.

Can you complete now as a check the annotations to explain how metamorphic rocks form? Pause a video and come back when you've had a go.

Hopefully you added these two words.

Heat from the mantel and core and pressure from the weight of overlying layers of rock.

Well done.

Another quick check for you.

Rocks do not change once they are formed.

Is this true or false and why? Pause the video and come back when you've decided.

I hope you said false.

And your reason for that is that metamorphic rocks are created by heat and pressure acting on sedimentary rocks and igneous rocks.

Well done.

Let's have a go now at our first task.

Can you complete this summary table for the three main rock types that we find in the UK? Igneous, sedimentary, and metamorphic.

Think about how they're formed, their main characteristics, and any examples that you can remember and come back when you've had a go.

Your table may look something like this.

Igneous, how is it formed from cooled magma and lava.

Characteristics, it is hard, it's crystalline, does not have fossils, and it's generally impermeable.

Example would be granite.

Sedimentary, layers of sediment, sand, mud, dead plants and animals are compacted and compressed over time.

Characteristics being it's layered, it's softer, it's may have fossils and it's often permeable.

Examples include limestone and chalk.

Metamorphic, heat and pressure acts on existing rocks changing their structure.

Characteristics are that it's very hard, it's resistant to erosion, it's generally impermeable, and it has a crystalline structure.

Examples include gneiss, slate, and marble.

Well done if your table looks similar to this one.

Let's move now to our second learning cycle for today's lesson.

The distribution of the UK's main rock types.

The rocks and landscapes of the UK were formed over hundreds of millions of years, and they've been shaped by natural processes including tectonic activity, volcanic activity, and sea level changes.

You can see that over the last 300 million years between the Permian and the quaternary period, the UK has moved from its position near the equator where it was covered by tropical seas north to its current position and this is due to tectonic plate movements.

So the UK's geological past involved tectonic activity 300 to 400 million years ago, and this caused a volcanic activity which formed igneous rocks like granites.

And we can see the red areas on the map that you can see correspond to some of the upland areas found in the UK by looking at that relief map.

We know that we had mountain building events that formed the Scottish Highlands and the Lake District and heat and pressure that created metamorphic rocks took place alongside this tectonic activity and it created rocks such as slates and gneiss.

And we can see that the blue areas on the UK's geology map indicate where we find metamorphic rocks.

So the UK has also been found beneath warm shallow seas.

And here sediments will have built up to form sedimentary rocks over time.

For example, chalk and limestone.

And we can see that the sedimentary rocks are shown by the yellow colour on this geology map.

True or false for you now then.

Tectonic activity in the UK's geological past has influenced its geology.

And why? Can you provide a reason for your answer? Come back when you've made your decisions.

I hope you said true.

And your reasons being something similar to this.

Past plate collisions caused mountain building.

For example, the Scottish Islands, the Lake District, and also led to volcanic activity which formed igneous rocks like granite.

Heat and pressure during these events created metamorphic rocks such as slate and schist.

Well done if your answer was similar to that one.

So as a result of this, the geology of the UK is very varied and we can see here that the oldest geology, igneous and metamorphic rocks, are in the northwest and the youngest geology, sedimentary rock, is in the southeast.

So much of the UK is made of sedimentary rock because ancient sea once covered these land areas.

Some examples of this include Peak District has a large limestone area and the Southeast of England has chalk on the South Downs.

Which of these regions in the UK do sedimentary rocks types dominate? South Downs, Dartmoor, Peak District, Scottish Highlands, for example, the Cairngorms. Pause the video and decide on your answers.

Hope you correctly identified the South Downs and the Peak District as being areas where sedimentary rocks types dominate.

The South Downs having the chalk and the Peak District, the limestone.

Igneous rock is found in several parts of the UK mostly upland areas where there was once ancient volcanic activity.

Dartmoor show has an example of granite tors, and the Scottish Highlands.

For example, the Cairngorms, the artist Skye, and Ben Nevis.

These upland regions consist of granite and basalt, which are a type of igneous rock.

Metamorphic rocks are mainly found where ancient tectonic activity cause high heat and pressure, which is able to change existing rocks.

Examples of it include the slate found in North Wales and rocks found in the Scottish Highlands.

For example, the schist of Ben A'an.

Check for you now.

In which of these regions in the UK would you be most likely to find igneous rock? A, the South Downs, B, Dartmoor, C, the Peak District, or D, the Scottish Highlands, for example, the Cairngorms. Pause a video and come back when you've made your decision.

I hope you correctly said Dartmoor and the Scottish Highlands.

Another check for you now.

In which of these regions in the UK would you most likely be able to find metamorphic rock? North Wales, Dartmoor, the Peak District, or the Scottish Highlands? Pause the video and come back when you've decided.

I hope you correctly said North Wales and the Scottish Highlands.

Well done.

Let's move now to task B in today's lesson.

On this map of the UK, I'd like to shade areas of igneous rock in red, sedimentary rock in yellow and metamorphic rock in blue.

Secondly, can you annotate the map to give a reason for the different rock types? Pause the video and come back when you've had a go at completing this.

I hope your annotated map will look like a simplified version of this GIS layer.

So pointing to the metamorphic rocks.

These regions experienced intense heat and pressure during past tectonic collisions, changing existing rocks into metamorphic rocks like schist and slate.

Pointing to an area of igneous rocks.

These areas were once sites of volcanic activity, magma cooled and hardened forming igneous rocks like granites.

And then pointing to the area of sedimentary rocks.

These lowland areas were once covered by warm shallow seas.

Over time, layers of mud, shells, and sea creatures built up and form sedimentary rocks like chalk.

Well done if you have something similar to this.

Let's look now at a summary of today's lesson.

The UK has three main rock types, igneous, sedimentary, and metamorphic.

Igneous rocks are hard and impermeable and found in volcanic uplands.

For example, Scotland and Dartmoor.

Sedimentary rocks are softer, layered, permeable and common in lowlands like Southeast England.

Metamorphic rocks form under heat and pressure and are found in mountainous areas.

For example, the Scottish Highlands.

Rock distribution reflects the UK's geological history of volcanoes, tectonic activity, and sea level changes.

Well done.

I hope you now feel more confident in describing the characteristics and distribution of the three main types of rock in the UK.

I look forward to seeing you again soon.