An earthquake is a shaking and vibration of the ground caused mainly by the sudden breaking and movement of the tectonic plates in which the Earth's crust is subdivided or by volcanic activity. Tectonic plates can include continental crust, oceanic crust or both; the earthquakes are usually concentrated along the edges of plates.
Potential damage in an earthquake can be produced by the following main hazards: ground shaking, ground displacement, tsunamis, flooding, landslides, fires etc.
Today, earthquakes prediction is not possible; nonetheless, scientific studies include activities aimed at understanding the mechanisms of the seismicity and assessing the probability of an earthquake.
Prepared by CERG - European Centre on Geomorphological Hazards - Strasbourg, France & the Editorial Board