GCSE Revision - Reducing the impacts of Earthquakes & Volcanoes

Why do so many people live in areas where earthquakes and Volcanoes take place?
The following refer in some cases to both or either of the hazards.

  • Volcanoes produce fertile soils when the lava weathers

  • Many volcanoes have been dormant for hundreds of years

  • Jobs are provided in the tourist industry - many like to visit volcanoes and geysers - it provides work in tourist shops, hotels etc

  • Volcanoes can produce minerals such as pumice, sulphur and even precious stones

  • Hot springs and baths and heating such as in Iceland where large open baths are found and central heating is provided

  • In some areas the heat can produce electricity

  • People live in earthquake areas such as San Francisco because it is a desirable area and people were unaware of the theory of plate tectonics until recently

  • Some people have the belief that neither of the hazards will affect them!!!!!

A Geyser - Tourist Attraction

The Blue Lagoon in Iceland
Swimming pool & Making Electricity

Tourists watching Mt Etna erupt


What can be done to reduce the impacts of Earthquakes?

     Despite much research it is not yet possible to predict earthquakes accurately - The best advanced knowledge is 9 seconds which is too short to do anything. Therefore most efforts have been put into preparing for them. Below are some of the ways:

  • Earthquake Resistant Buildings - These are built with deep foundations with rubber shock absorbers and concrete reinforced with steel. They are designed to twist and sway, have sprinkler systems and gas cut off valves

  • Emergency Plans - These are drawn up, and supplies such as bottled water, medicines, tinned food etc are stockpiled by individuals or the local area

  • Earthquake Drills - These are held to practise what to do in the event of an earthquake taking place such as the one held in Japan on Sept 1st every year.

  • Tsunami Warnings - As Tsunamis occur in the Pacific Ocean there are data collecting devices to give warnings of such an event. They are also being built in the Indian Ocean.

What can be done to reduce the impacts of Volcanoes?
 

Prediction

Technological advances are making it easier to predict volcanic eruptions.

  • Satellites monitor the temperature and shape of active volcanoes.

  • Sensors measure levels of sulphur dioxide and carbon dioxide gas

  • Seismometers record earthquakes as magma rises to fill the volcano

  • Tilt meters record any change in the shape of the volcano

  • Volcanoes can be studied similar to an organ pipe and for the increase in pressure prior to an eruption

Preparation

Being able to predict volcanic eruptions makes it easier to prepare for them

  • Hazard maps are drawn up to show areas at risk

  • People are evacuated to safe areas.

  • Lava flows may be diverted by spraying them with water, or even bombing them

  • Emergency services can be trained to be ready for an eruption and deal with injuries etc

  • Emergency supplies can be got ready such as food, water etc

  • Provide an after eruption plan to return the area to normal with plans for clearing up the mess and repairing the damage.