Epicenter

Earthquakes can cause large amounts of death and destruction. For this reason, understanding them is of vital importance for the inhabitants of the communities. Like all major events, seismic or otherwise, they have to start somewhere. The epicenter is the place on the Earth’s surface where earthquakes begin and are generated .

It is generally the place where the waves of an earthquake are most intense and, as a result, it is also the place with the most damage . But this can sometimes change. If an earthquake is particularly large, it can pass through a large section of the plate boundary. In this case, the epicenter could be just one of many locations of the places with the most damage, and the damage could be greater elsewhere.

Epicenter etymology

The word epicenter is made up of two words of Greek origin. The first ” ἐπί ” pronounced as epi, has the meaning ” on ” and the second word ” κέντρον ” has the meaning center . The term was coined in 1880 by Irish-born geophysicist Robert Mallet .

Damage to the epicenter

It should be remembered that the epicenter is the geographical point located closer to the focus of the quake and it generally tends to be the area most affected of all. It is the point inside the earth where the tremor originates and where the waves generated by the movement begin . It is generally the place that suffers the greatest damage to infrastructure, including loss of human life.

Epicentral distance

One of the main functions of the tasks carried out by a seismological observatory is the location of both the epicenter and the epicentral distance to determine the origins of the seismic sources. The epicentral distance is the distance between its hypocenter and the places where seismic waves propagate during the event. It can also be defined as the distance between a person and the place where the epicenter of the earthquake takes place, measured on the surface of the earth.

Importance

The main importance of determining the epicenter is that the fault that broke or that has mobilized causing the earthquake can be identified . If the fault is recognized, then the earthquake can be used to augment or modify, if necessary, the risk modeling for the area that has been affected. If the fault is previously unknown then it is important because it means that the hazard models for the affected area need improvement.

When the epicenters are known, building codes focus on mitigating the expected risks. Therefore, risk models for an area are built on the basis of hazards that have been previously identified, and risks that are considered unlikely to occur tend to be left out of the models.

It is also important because when the epicenter of an earthquake is known, it is known that the area is prone to suffer from such events and manages to take decisions regarding the codes of construction of buildings to avoid future disasters.

Examples of epicenter

• Chile earthquake on May 22, 1960. With an intensity of 9.5, its epicenter was located in the city of Valdivia and it was the earthquake with the highest intensity that has been recorded on the planet.
• Earthquake in Indonesia , the epicenter of which occurred in Sumatra on March 28, 1964. It produced a rising of the soil on the continent.
• Earthquake in Japan on March 11, 2011. Its epicenter was on the coast of Honshu and caused a tsunami that affected waves of 2 meters high. It caused the axis of the earth to move 10 centimeters. The Fukushima nuclear accident occurred
• Peru earthquake on August 13, 1868. Its epicenter was located in Arica and could even be felt in Bolivia. It caused a tsunami that also affected the coasts of California, Hawaii and the Philippines.
• Earthquake in South Carolina , United States , whose epicenter was in the same place on Tuesday, August 31, 1886 at 9:50 pm In 6 to 8 minutes, the earthquake was felt in Philadelphia , New York , Chicago and Louis . In the Charleston area, 100 people died as a result of the earthquake, houses cracked and collapsed, beds of sand explosively expanded in the air and produced craters with surrounding blankets of ejected sand. The magnitude of the earthquake was estimated between 7.0 and 7.7 .