On July 29, 2008 Los Angeles was hit with a moderate earthquake. This 5.4-magnitude quake made buildings sway, sent people running into the streets and rattled lamps. This earthquake was felt as far as Las Vegas which is 230 miles away. Following this quake were 30 aftershocks, the largest estimated at 3.8. Minor damages were reported in Los Anglees along with five injuries.

Earthquakes are caused due to a sudden release of energy in the Earth's crust that creates seismic waves. Earthquakes manifest themselves by shaking or even displacing the ground. Seismometer, which is used to record earthquakes, tells us the magnitude of an earthquake. An earthquake with a magnitude of 3 or lower hardly causes any damage. One with a magnitude of 7 causes severe damage over large areas. Ruptures of geological faults, huge amounts of gas migration, volcanic activity, lanslides, mine blasts and nuclear experiments are the causes of earthquakes. Humans can also cause earthquakes by the construction of large dams and buildings, drilling and injecting liquid into wells, and by coal mining and oil drilling. Most of the earthquakes take place at a horse-shaped zone called the circum-Pacific seismic belt, or also known as the Pacific Ring of Fire.

The natural occurrence of earthquakes is caused where there is sufficient stored elastic strain energy to drive fracture propagation along a fault plane. These planes will move past each other smoothly unless there are irregularities along the boundary that cause an increase in the frictional resistance. If there are irregularities then this leads to the formation of the stick-slip behavior. As the plates keep moving they start to stick, eventually increasing stress around the fault surface. This continues until the stress breaks, allowing sliding over the locked portion of the fault surface, cracking the rock and thus creating an earthquake. This process is called the Elastic-rebound theory.

Earthquakes can cause landslides, fires, tsunamis, and floods. People are also impacted by earthquakes. Earthquakes cause disease, higher insurance premiums, property damage, collapse of buildings, and the most significant one is the human life. There are several ways in which on can prepare for an earthquake. People are encouraged by the governments to have an earthquake kit in their homes. Also people should move their heavy and dangerous objects to low places and secure their bookshevles that could topple into the wall. Free standing natural gas stoves and appliances using natural gas should be restrainted efficiently.

Sara Jane