The recent and continuing earthquakes in Indonesia are a result of the country’s location on a fault line. There earthquakes all over the country during the year, most of which shake up the locals a bit but do not cause much damage. Just today 11 earthquakes shook Sumatra, where just day ago 14 people lost their lives in a 7.9 quake.
An earthquake is the result of a sudden release of stored energy in the Earth’s crust that creates seismic waves. Earthquakes are accordingly measured with a seismometer, commonly known as a seismograph. The magnitude of an earthquake is conventionally reported using the Richter scale or a related Moment scale (with magnitude 3 or lower earthquakes being hard to notice and magnitude 7 causing serious damage over large areas).
At the Earth’s surface, earthquakes may manifest themselves by a shaking or displacement of the ground. Sometimes, they cause tsunamis, which may lead to loss of life and destruction of property. An earthquake is caused by tectonic plates getting stuck and putting a strain on the ground. The strain becomes so great that rocks give way by breaking and sliding along fault planes.
Earthquakes may occur naturally or as a result of human activities. Smaller earthquakes can also be caused by volcanic activity, landslides, mine blasts, and nuclear experiments. 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.
An earthquake’s point of initial ground rupture is called its focus or hypocenter. The term epicenter means the point at ground level directly above this.
Here’s more from the Jakarta Post
Here in Bali we did not feel anything.
