A technician of the National Service of Territorial Studies shows a graph after an earthquake, in San Salvador, capital of El Salvador, Nov. 7, 2012. A magnitude 7.4 earthquake affected El Salvador on Wednesday. The epicenter of the quake was 24 kilometers south of Champerico in Guatemala, according to the U.S. Geological Survey. (Xinhua/Oscar Rivera)

A technician of the National Service of Territorial Studies shows a graph after an earthquake, in San Salvador, capital of El Salvador, Nov. 7, 2012. A magnitude 7.4 earthquake affected El Salvador on Wednesday. The epicenter of the quake was 24 kilometers south of Champerico in Guatemala, according to the U.S. Geological Survey. (Xinhua/Oscar Rivera)

A technician of the National Service of Territorial Studies shows a graph after an earthquake, in San Salvador, capital of El Salvador, Nov. 7, 2012. A magnitude 7.4 earthquake affected El Salvador on Wednesday. The epicenter of the quake was 24 kilometers south of Champerico in Guatemala, according to the U.S. Geological Survey. (Xinhua/Oscar Rivera)