[ e a r t h q u a k e s   :   s i d e   e f f e c t s ]

The shaking of the earth can cause other natural disasters as well. In the mountains, such plate movement can cause snow or rock masses to slide downhill in the form of landslides or avalanches. “Soil liquefaction,” or the transformation of seemingly solid earth into a thick liquid when wet, occurs when sandy soil is vibrated (such as during an earthquake). The sand particles are shaken apart, giving the wet quicksand the consistency of porridge. Many buildings, such as those in Niigata, Japan in 1967, were knocked onto their backs as a result of soil liquefaction. During this same earthquake, residents found themselves sinking in the fluid soil. No one drowned, however, because the quicksand-like earth allowed people to float. However, 26 people did die when the earthquake crashed 3,000 homes.

Another earthquake side-effect is a phenomenon known as debris flow - a thick soup of water, soil, rocks, and boulders resembling freshly mixed concrete. One mother stood with her two children on a stormy February night in 1978 in Los Angeles, California (United States). She described the sight as “one big black thing coming at us, rolling, rolling with a lot of water in front of it, pushing the water, this big black thing.” The debris flow crashed into their house moments later. The heavy silt also deposited numerous automobiles around the building and left a twelve-foot-high pile of muddy rubble in the yard. The dirt entered the house through windows and doors, but the family escaped with their lives. Debris flows are common near the San Gabriels, a stretch of mountains ranging eastward along Los Angeles. They are among the world’s newest and most unstable mountain ranges, still pushing upward while losing pieces of their sides. Winter rains also lubricate the shaky earth and send it down into the city. In order to prevent major damage, local officials have dug 120 large pits on the hillsides, with concrete pillars set above them to stop larger rocks. However, the storming earth often pours over these defenses and crashes down to the buildings below. One such city is Pasadena, where a reservoir originally built to store water is now full of mountain sand and gravel.

Beneath the ocean, undersea earthquakes (known as seaquakes) can also trigger huge waves, known as tsunamis (link to Tsunami section), which can travel as quickly as a jet airliner (up to 500 miles an hour). Also known as tidal waves, they can also be caused by coastal land earthquakes. Tsunamis occur most frequently in the Pacific and Indian oceans. The enormous force of a tidal wave builds up a huge wave crest in a giant wall of water, often over 100 feet high. After crashing inland, it can drown and sweep away everything in its way. They often flood coastal regions.

[ info ]: introduction - legends - what are they? - the causes - where do they occur? - earthquake strength - side effects - aftershocks - earthquake damage - prediction - preparation - prevention - references - glossary

[ reality ]: current events - case studies - ten worst - real life stories - interviews - quotations

[ interact ]: multimedia - simulations - classroom - activities - quizzes - message board - resources

[ general ]: about - win our award - awards we've won - guestbook - help - contact us - sitemap

[ forces ]: avalanches - droughts - earthquakes - flooding - fog & mist - forest fires - hurricanes - landslides - monsoons - phenomena - severe storms - snowstorms - tornadoes - tsunamis - volcanoes - windstorms - main page