An earthquake (also known as a tremor or temblor) is the result of a sudden release of energy in the Earth's crust that creates seismic waves. Earthquakes are recorded with a seismometer, also known as a seismograph. The moment magnitude of an earthquake is conventionally reported, or the related and mostly obsolete Richter magnitude, with magnitude 3 or lower earthquakes being mostly imperceptible and magnitude 7 causing serious damage over large areas. Intensity of shaking is measured on the modified Mercalli scale. At the Earth's surface, earthquakes manifest themselves by shaking and sometimes displacing the ground. When a large earthquake epicenter is located offshore, the seabed sometimes suffers sufficient displacement to cause a tsunami. The shaking in earthquakes can also trigger landslides and occasionally volcanic activity. In its most generic sense, the word earthquake is used to describe any seismic event—whether a natural phenomenon or an event caused by humans—that generates seismic waves. Earthquakes are caused mostly by rupture of geological faults, but also by volcanic activity, landslides, mine blasts, and nuclear experiments. An earthquake's point of initial rupture is called its focus or hypocenter. The term epicenter refers to the point at ground level directly above the hypocenter
What can you expect to happen?
Earthquakes happen without warning. They can happen any time of day, at any point during the year. Almost all place in Andaman & Nicobar Island can experience earthquakes, both small and big. Sometimes an earthquake will be so small you’ll barely feel it. Other times an earthquake will cause the ground to shake so much that buildings and bridges collapse. Fires, landslides, avalanches, and flash flooding might even happen.
Stay alert for aftershocks, which are smaller earthquakes that follow the main one. Aftershocks could happen within a few hours of the main earthquake, or they could happen weeks or months later.
You will never have warning that an earthquake is coming. To make sure you and your house are prepared, you should:
Here are some tips of what to do during an earthquake:
After the earthquake stops, here’s what you should do: