An earthquake is a sudden shake of the earth's crust that occurs unexpectedly. The earthquake, has its origin in a point inside the Earth called a hypocentre or focus, which is normally located less than 50 km deep, because if it is below that level, the earthquake does not usually reflect on the outside.
The point corresponding to the perpendicular of the hypocentre on the surface is the epicentre, where the earthquake registers its maximum intensity. The hypocentre generates waves, the seismic waves, which propagate on the surface, losing intensity as they move away from the epicentre.
The magnitude of an earthquake values the amount of energy released in the focus at the time it occurs. To measure the magnitude of earthquakes is used a scale of ten degrees developed by the American seismologist C. F. Richter. The intensity of an earthquake is based on the evaluation of the effects produced by seismic waves in the affected area. The intensity was measured using a twelve-degree scale created by the Italian G. Mercalli, which was slightly modified in 1964. These and other important characteristics of earthquakes (amplitude, duration, time, etc.) are reflected in the seismograph, which is a device that records seismic waves.
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The point corresponding to the perpendicular of the hypocentre on the surface is the epicentre, where the earthquake registers its maximum intensity. The hypocentre generates waves, the seismic waves, which propagate on the surface, losing intensity as they move away from the epicentre.
The magnitude of an earthquake values the amount of energy released in the focus at the time it occurs. To measure the magnitude of earthquakes is used a scale of ten degrees developed by the American seismologist C. F. Richter. The intensity of an earthquake is based on the evaluation of the effects produced by seismic waves in the affected area. The intensity was measured using a twelve-degree scale created by the Italian G. Mercalli, which was slightly modified in 1964. These and other important characteristics of earthquakes (amplitude, duration, time, etc.) are reflected in the seismograph, which is a device that records seismic waves.
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