Aftershocks occur within the first hour of the main shock of an Earthquake, which decreases in magnitude with every subsequent shock. Aftershocks are normally of a lesser magnitude than the main shock of Earthquakes and they come in a cluster one after the other after the main shock has stricken. The aftershocks occur very close to the place, which is hit by the earthquakes. Earthquakes are often referred to as the aftershocks when there is no big difference between the magnitude of the earthquake and the aftershocks.

Nature of Aftershocks

The rate of the aftershocks decreases with passing time. Earthquakes of a great magnitude, which have a very devastating effect, are also followed by equally powerful aftershocks. Earthquakes are one of the most destructive Weather-related disasters and the aftershocks sometimes last till the next day too. It is best to know about the presence of these aftershocks so that the inhabitants of the place hit by an earthquake can be alert beforehand.

Causes of Aftershocks

The aftershocks are basically earthquakes of a smaller nature and the cause of this is that that the plate boundaries, which got displaced, take time to come back to its original position. The pattern, which is followed by an aftershock, is measured by Omori's Law, the modified version. The law states that the rate of the aftershock is proportional to the inverse of the time since the main shock has occurred.

The most disadvantageous part about these aftershocks is that they cannot be predicted. So they can be quite dangerous as they hit without any warning, especially when the victims think that they are safe.