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What is an Earthquake

What is an Earthquake
Introduction to Earthquakes & Tsunamis Turn on the TV or read the newspapers and almost always there is something devastating happening somewhere as a result of sheer nature's power. Examples of such natural occurrences are hurricanes, tornados, wildfires, volcanic eruptions, flooding, earthquakes and tsunamis. These are usually not caused directly by humans, but their effects live with us for a long time. In this lesson we shall look at one of such natural occurrences...earthquakes! What is an Earthquake? Simply, earthquakes are the rumblings, shaking or rolling of the earth's surface. Earthquakes come in many forms. Foreshocks, Mainshocks and Aftershocks: Sometimes, there are smaller shocks that occur before (foreshock) and after (aftershock) a main earthquake (mainshock). Earthquakes are also called temblors. It is important to understand the earth’s makeup to help understand earthquakes better. The Mantle is semi-molten rock, also called magma.

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Disasters - preparedness/Civil Defence Image: Earthquake survival kit by Global X on Flickr We have selected these online resources to support you when you need information relating to civil defence and preparing for disasters. SCIS 1702159 See also Earth science - Volcanoes; Earth science - Tsunami; Disasters - Natural; Disasters – New Zealand; Extreme weather The Environmental Protection Agency in the United States lists ways to reduce risks to health and the environment from natural disasters. Suggested level: intermediate,

Earthquake! ©1995 The Regents of the University of California (576K) Earthquake Picture- Walking the line- Click for bigger version Introduction Earthquakes are one of the most powerful natural forces that can disrupt our daily lives. What is a flood? Introduction to Flooding Many of us have this idea that floods (or flooding) is simply, too much water around your house. People think that can be fun. Why Was the Destruction So Severe? Six weeks after the Haiti shock, Chile was struck by an 8.8-magnitude earthquake. It was 500 times more powerful than the Haiti quake, yet killed less than 1% of the Haitian total. In this section, we explore answers to the question: why was the Haiti earthquake so destructive? This Flash piece is 525 x 372. To embed it in your site, copy and paste the following code. <script type="text/javascript"> var file="destruction_slideshow.swf"; var width = 525; var height = 372; </script><script type="text/javascript" src="

Earthquake Facts The origin of the name of the San Andreas Fault is often cited as the San Andreas Lake. However, based on some 1895 and 1908 reports by geologist A.C. Lawson, who named the fault, the name was actually taken from the San Andreas Valley. He likely did not realize at the time that the fault ran almost the entire length of California! Hazard: Earthquake/Be smart Map Information: The map is titled, "Forecasted Frequency of Earthquake Shaking Capable of Causing Damage Within the United States". It depicts a map of the continental United States, Puerto Rico, Alaska, and Hawaii and illustrates state and county boundaries. The intensity of forecasted shaking (corresponding to level VI on the Modified Mercalli Intensity scale) is capable of the following: cracking windows; knocking dishes, glassware, knickknacks, and books off shelves and pictures off walls; moving or overturning furniture; and cracking weak plaster, adobe buildings, and some poorly built masonry buildings. Data source is the USGS National Seismic Hazard Mapping Project, updated in the following years: contiguous US-2014, Alaska-2007, Hawaii-1998, Puerto Rico and the US Virgin Islands-2003; forecasted frequency of a horizontal ground acceleration on firm rock of at least 7.2% g, which is an average acceleration corresponding to an MMI of VI.

Natural Disasters 1. Most natural disasters are caused by weather. Weather disasters can be caused by hurricanes, tornadoes, floods, tsunamis, thunderstorms, wind storms, wildfires, avalanches, and blizzards. Weather Wiz Kids weather information for kids Earthquakes(Earthquakes are not associated with weather, but instead are natural disasters.) What is an earthquake?Earthquakes are the shaking, rolling or sudden shock of the earth’s surface. They are the Earth's natural means of releasing stress. More than a million earthquakes rattle the world each year. The West Coast is most at risk of having an earthquake, but earthquakes can happen in the Midwest and along the East Coast.

Faultline: Theory of Plate Tectonics The answer is that some places on the earth's surface are, literally, on the edge. During its early years, the earth's outer layer was much hotter than it is today. Over time, the surface of the earth cooled and hardened. Earth Structure: Earthquakes Rumble rumble rumble! Have you ever been in an earthquake? Some people go through them all the time. In California there are dozens every day but they are usually very small. You tend to remember the big ones. What is a volcano? Introduction to volcanoes The earth's mountains, plains, plateaus, soils, rocks, etc. as we see it today is believed to have gone through many phases, with about 80% of it being carved out by the action of volcanoes. A volcano is simply a rapture (opening or vent) on the earth's surface (crust) through which molten magma (extremely hot mixture of gases, lava, ash and other burning substances) escape on to the earth's surface.

Documentary about regenerating large-scale damaged ecosystems Meet John D. Liu, the environmental film maker who says "it is possible to regenerate large-scale damaged ecosystems." The documentary film looks at restoration projects in China, Africa, South America and the Middle East, who aim to rejuvenate eroded landscapes. Permaculture teacher Geoff Lawton, who stars in the film states: "The world gets more and more complicated all the time but the solution to fix the major problems of the worlds ecosystems remains reasonably simple. We have to go ahead on a major scale now. Everybody can do their back yard but we have to change the major eroded landscapes into the functional ecosystems they should be."

Earthquakes Earthquakes are sudden rolling or shaking events caused by movement under the earth’s surface. Earthquakes happen along cracks in the earth's surface, called fault lines, and can be felt over large areas, although they usually last less than one minute. Earthquakes cannot be predicted — although scientists are working on it! All 50 states and 5 U.S. territories are at some risk for earthquakes. Earthquakes can happen at any time of the year.