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earthquake

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  1. earthquake An ABC news story archive from January 15, 2001 included this image. A huge landslide was triggered in the town of Santa Tecla, El Salvador following the 7.6 magnitude earthquake. The earthquake claimed some 600 people and damaged some 34,000 homes. This landslide buried hundreds of homes. The earthquake epicenter was some off the Salvadoran coast.

  2. The short answer is that earthquakes are caused by faulting, a sudden lateral or vertical movement of rock along a rupture (break) surface.     Here's the longer answer: The surface of the Earth is in continuous slow motion. This is plate tectonics--the motion of immense rigid plates at the surface of the Earth in response to flow of rock within the Earth. The plates cover the entire surface of the globe.

  3. The earth has “plates” and when two plates hit each other, one goes under and becomes “molten” which means it gets so hot, the ground turns into liquid. The molten stuff finds a hole in the ground and comes out the top. All of the continents used to be just one big piece of land, but the land broke up and floated away and created the 7 continents we have now.

  4. EFFECTS OF VOLCANOS A volcano is actually an opening or a fissure, in the earth' crust , through which lava or molten rocks, ash and toxic gases present below the surface of Earth, are discharged by a sudden, violent eruption. Sometimes, it can be a mountain like structure with a bowl shaped depression at the top, through which these substances are expelled.

  5. CAUSES OF LANDSLIDES Landslide damage from the Northridge earthquake was only moderate because the area of greatest landslide activity is not yet heavily developed. However landslides did, as described below, block roads; damage and destroy homes; locally disrupt water mains, sewers, and power lines; and damage oil- and gas-production facilities.

  6. The Thistle landslide (pictured on the right) was the most costly single landslide event in U.S. history with costs exceeding $400 million. Land began shifting in Thistle, Utah in 1983 because of groundwater buildup from heavy rains during the previous fall and the melting of deep snowpack from the winter. Within a few weeks, the landslide dammed the Spanish Fork River, destroying U.S. Highway 6 and the main line of the Denver and Rio Grande Western Railroad.