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This answer will explain how the occurrence of earthquakes can be predicted and their effects reduced. At present seismologists can predict where earthquakes are likely to occur; however, it is very difficult to predict when earthquakes might occur. Seismologists can only minimise the effects of earthquakes by identifying areas of high risk. Seismologists use a variety of measures to monitor and predict the occurrence of earthquakes. Seismologists examine the patterns of earthquake activity. By examining previous earthquakes, seismologists can predict the likelihood of another earthquake occurring. The longer the time since the last earthquake, the more imminent the next earthquake in the region. Areas along a faultline that have not experienced seismic activity for a long period are also monitored. These locations are referred to as seismic gaps and are likely locations for earthquakes. Laser beams are used to detect plate movement. Instruments called tiltmeters are also used to monitor and predict the occurrence of earthquakes. Tiltmeters record changes in the level of the land. When pressure is exerted on the crustal plates, an increase in the height of the land may occur. Early warning systems are being established using a global network of seismographs. These detect and signal immediate seismic waves. An increase in levels of radon gas may also suggest the occurrence of an earthquake as radon gas escapes through cracks in the Earth’s crust.

The collapse of infrastructure causes the greatest loss of life during an earthquake. By knowing where earthquakes are likely to occur, authorities can reduce the impact by investing in measures to ensure that buildings are built to withstand earthquakes. An example of such a measure is setting limits on the heights of buildings, e.g., Japan. In the United States authorities use earthquake risk maps to control land use in earthquake-prone areas and therefore, limit the effects of seismic activity. In wealthy countries many new buildings are built on roller foundations and are specifically designed to withstand strong tremors. These buildings are reinforced with steel bars and have shock absorbers to absorb the tremors of an earthquake. However, in poorer countries such as Haiti, authorities cannot afford to construct such expensive earthquake-resistant infrastructure; therefore, making it more difficult to reduce the impact of seismic activity. Another measure used to reduce the effects of earthquakes is educating people how to react in the event of an earthquake. In Tokyo, Japan, public awareness programmes are run to ensure that people are prepared for an earthquake. In earthquake-prone areas, earthquake drills are held regularly in schools.