how the occurences of an earthquake can be reduced

how do earthquakes occur

• earthquakes occur due to plate moment when tectonic plates become stuck and there is a sudden release of energy. This is how seismic waves are created

focus of the earthquake and epicentre

focus: the point below the earths surface where the quake originates

epicenre: the point directly above the focus of the earths surface - shaking is most intense here.

results in significant damage, even loss of life.

Pacifid ring of fire

• tectonically active region along the Pacific ocean

• earthquakes are frequent here

• e.gJapan

earthquake prediction

• can be defined as an attempt of forecasting the time, location and magnitude of future earthquakes before it happens

• unlike predicting weather, prediciting eartquakes is seen as a challenge and an ambitiious goal

• It is very difficult because of the unpredictability of tectonic plates and the nature of faults

seismologists and geoligists

• have developed various techniques to assess the likelihood of earthquakes that occur in specific regions over time

• . 1 monitering seismic activity

• using historical earthquake data

seisimic activity monitering

• constant monitering of seismic activity

• networks of seisometers are deployed in regions prone to earthquakes

• These isntruments measure the smallest vibrations in the earths crust known as seismic waves

• Seismologists can then analyse these waves and detect patterns or foreshocks that create larger earthquakes

• Howver not all foreshocks result in bigger earthquakes, making this method partially reliable

HIstory of earthquake data

• Estimates the frequency and strength of earthquakes in certain regions

• Geologists use past events to identify patterns which help create “seismic hazard maps” for areas prone to earthquakes

• These maps estimate the probability of an earthquake occuring by determining the seismic gap - how long since an earthquake has occured in the region.

• The larger the seismic gap the greater the probability of an earthquake.

early warning systems

• one of the ways in which earthquakes can be reduced.

• Countries like Japan, the USA and Mexico have developed early warning systems to detect primary waves (P waves) - the fastest seismic waves that travel through the earth;s crust

• These waves are followed by secondary waves (S waves) - these cause the most damage.

• Once P waves are deteced, emergency texts are sent to residents to warn them of a possible earthquake

• This allows people to take action and promotes automated shutdowns of power plants, transport systems and critical infrastructure to reduce potential damage and casualties.

earthquake resistant buildings

• one of the most effective ways to reduce the impact of earthquakes.

• Engineers have developed various different techniques to make structures more resistant to seismic forces such as flexible materials, shock absorbers and base isolaters.

• Base isolation: technique - building is placed on flexible pads that allow it to move independantly of the ground motion during an earthquake absorbing a lot of the seismic energy.

• earthquake resistant buildings - retrofitting existing strucures as many older buildings were constructed before modern earthquake resistant buildings were made which makes them more vulnerable to seismic damage.

Public educatedness

• education and preparedness are important for reducing the impact of earthquakes on communtiies.

• Governments and organisations provide publid education on what to do before, during and after an earthquake in earthquake prone regions.

• Such as advice on securing heavy furniture, creating emergency plans, assembling kits with food, water, first aid and supploes.

• Earthquake drills in schools, workplaces and communities help people understand how to respond quickly and effectively in the event of an earthquake.

• E,g Japanese governement using historical data, publishing hazard maps to show tsunami prone and earthquake prone areas. They also have regular evacuation drills in zones at risk.