Physical Geography- Prediction and Effects of Earthquakes

Explain how the occurrence of earthquakes can be predicted and how the effects of earthquakes can be reduced with reference to examples you have studied

An earthquake is the shaking or vibration of the Earth's crust. Earthquakes occur due to the movement of tectonic plates where the crust is under extreme pressure. Scientists have developed different methods of earthquake prediction to allow people enough time to prepare for the negative effects. Seismologists study the seismic history of the region because as soon as one earthquake occurs, pressure and tension begins to build up again. They also look for patterns of seismic activity to calculate the likelihood of an earthquake occurring. The longer the time since the last earthquake, the more imminent the next one is. Instruments called tiltmeters record changes in land levels. A bulge in the land may indicate a build up of pressure on the plates. Scientists may also look for signs of disturbance like foreshocks. Animal behaviour may also predict earthquake activity as animals tend to behave strangely before an earthquake.

The ability of a country to limit the effects of earthquakes is directly linked to its level of economic development. Developed countries will often have earthquake-proof buildings in regions prone to earthquake activity. These buildings use flexible columns to allow for movement. Building construction and bridges in these regions will be fire-proof. The buildings will be constructed on stable ground where liquefaction is not possible. Also, they region will regularly practice evacuation and safety plans to reduce deal with emergencies. These resources are much less available in developing countries.

An example of an earthquake I have studied is the Haitian earthquake of January 2010. This earthquake occurred on January 12 and measured 7.0 on the Richter Scale. Its epicenter was 25km west of Port-au-Prince. The effects of the earthquake were felt in several countries, including Jamaica, Cuba, Puerto Rica and the Dominican Republic. The earthquake occurred on the boundary between the Caribbean and the North-American Plate. As Haiti is a developing country, they were not well equipped to deal with an earthquake of this magnitude. Since the earthquake, over 200,000 people have been affected by cholera. The earthquake damaged infrastructure, which made it difficult to disperse aid. It is estimated that 300,000 died, over 300,000 were injured and 1 million were left homeless. Following the earthquake, seismologists started to examine the building up of pressure along the fault line to predict and reduce the effects of future earthquakes.