1. Year 9 Geography Revision

2. What is the Earth made up of?
The earth is just like a giant apple. It has a thin layer called the crust, a softer part called the mantle and a liquid centre called the core.
Some time after the earth formed, it got so hot that everything inside it melted. The heavier substances in the liquid sank and the lighter ones rose, forming layers. As the earth cooled, most of the layers turned solid.
Earth was formed 4,600 million years ago. Since then it has been slowly cooling down and a thin crust has formed round the outside.
The crust is broken into several enormous sections. The plates float above hot molten. The place where 2 sections/plates meet is called a plate boundary. The movement of these plate cause volcanoes & earthquakes.
Earthquakes
An earthquake is a sudden and short period of intense ground shaking.
1. Mercalli Scale
The earthquakes intensity is split into twelve groups.
Roman numerals I to XII are used to show the effects.
It is based on observation and opinions.
2. Richter Scale
This measures seismic waves using a seismograph.
The Richter scale is logarithmic: an earthquake measured at 7 is 10x stronger than that at 6.
Numbers range from 0 to 9

3. Volcanoes Earthquakes start at the focus.
The epicentre is the point on the Earth’s surface above the focus, and is the first place to shake.
The focus can be shallow or deep.
Underground tectonic plates push past each other, building up pressure.
This pressure is suddenly released along faults (cracks in the crust), sending out a huge pulse of energy.
This travels out in all directions as earthquake waves.
Volcanoes
A volcano has different parts to it. It grows and each is different, but they all have certain features including a chamber, a vent and a crater. When they erupt, it can cause many problems for the people who live there. We saw that many people died when Mount Vesuvius erupted, but there was a sequence from not seeming too bad, to everything destroyed. People have their own reasons for living near to them. These include:
1. They have always lived there.
2. They don’t think it will happen to them.
3. The fields are very rich in plant foods from the ash.

4. Criminal Geography
Crimes happen, but they have a pattern to them, which is all about where they
take place, in other words, the Geography of crime. In year 7, we saw that there
are different parts to a city or town, and revisited this information.
These are the CBD (also known as the city centre), the inner city,
the inner suburbs, and the outer suburbs.
Different crimes happen in these areas, depending on the type of building,
and the type of crime committed. For example, most shoplifting takes place in the CBD,
but most house burglary happens in the inner city from terraced houses.
The main types of houses are:
Terraced
Semi-detached
Detached
Flats (although these are often in older larger houses when they have been split up)
We have studied at least 14 crimes, what they are, where they are more likely to
take place, and the reasons why. These were:
Murder
Forgery
Vandalism
Armed robbery
Burglary
Domestic violence
Internet fraud
Handling stolen goods
Traffic offence
Environmental crime
Terrorism
Common assault
Car theft
Mugging
However, we discovered that crimes are able to happen in any area.
The police try to understand the criminal’s mental map
(those areas they feel more able to attempt the crime),
and try to prevent them happening.
This is called crime prevention, and it is something everyone can do.
Ways include more CCTV, walking in well-lit areas,
keeping your belongings close to you, and fitting secure locks.