VolcanoesJACQUELINE AMERS

Volcanoes

• A volcano is an opening or rupture, in the surface or crust of the Earth or a planetary mass object, which allows hot lava, volcanic ash and gases to escape from the magma chamber below the surface.

Highlights of Arenal: one of the 10 most active volcanoes in the world

How volcanoes are formed• Deep inside Earth,

between the molten iron core and the thin crust at the surface, there is a solid body of rock called mantle. When rock from the mantle melts, moves to the surface through the crust, and releases pent-up gasses, volcanoes erupt.

Continuation… • Extremely high

temperature and pressure cause the rock to melt and become liquid rock or magma. When a large body of magma has formed, it rises through and the denser rock layers toward Earth’s surface. Magma that has reached the surface is called lava.

Where volcanoes are located

There are more than 1500 active volcanoes on the Earth. We

currently know of 80 or more which are under the oceans.

• Active volcanoes in the U.S. are found mainly in Hawaii, Alaska, California, Oregon,

and Washington.

Types of Volcanoes

Effects of volcanoes• The effect an eruption will

have on a nearby city could vary from none at all to catastrophic. For example, atmospheric conditions might carry ash away from the city or topography might direct lahars and pyroclastic flows to unpopulated areas. In contrast, under certain atmospheric, eruption and/or topographic conditions, lahars, pyroclastic flows, and/or ash fall could enter the city causing death and destruction

Benefits • many of the volcanic

materials have important industrial and chemical uses.

• A natural glass that comes from lava is pumice, it is widely used for grinding and polishing metals, stones, and other materials. When lava dries and makes a rock form it is commonly used in building roads.

• Volcanic ash that has been weathered greatly improves soil fertility

• Volcanic material has a source of precious gems, Opal. It also has a source for metals, gold, silver, molybdenum, copper, zinc, lead, and mercury. When volcanoes erupt, the lava releases some healthy gases, including carbon dioxide and hydrogen. When oxygen mixes with hydrogen, it creates water vapor and that begins the water cycle.

Volcanic Issues• What happens to the towns

around a volcano when it erupts depends on many things. It depends of the size and type of eruption and the size and location of the town. A few examples might help. The 1984 eruption of Mauna Loa in Hawaii sent lava towards Hilo but the eruption stopped before the flows reached the town.

• The 1973 eruption of Heimaey in Iceland buried much of the nearby town of Heimaey under lava and cinder. The 1960 eruption of Kilauea in Hawaii buried all of the nearby town of Kapoho under lava and cinder

Solution• There is not a way to

stop volcanoes from erupting, making their no solution for volcanoes. However you can do many things to protect yourself and your family from the dangers a volcanic eruption can cause.

• The best way to protect yourself is to follow the advice of local officials. They can help and provide you with information in ways to prepare for a volcanic eruption, and if necessary, on how to evacuate or take shelter where you are, according to the CDC (Centers for Disease Control and Prevention).

Sources• • Learner, Annenberg. “Volcanoes. Interactivities. Annenberg Learner Acitivies,

2013. Web. 14 Oct. 2013 <http://www.learner.org/interactives/volcanoes/>• • Volcano World | Your World Is Erupting." Volcano World | Your World Is Erupting.

Oregon Space Grant Consortium, n.d. Web. 14 Oct. 2013.• • Volcano Hazards Program." Volcano Hazards Program. U.S. Department of the

Interior, Oct.-Nov. 2013. Web. 14 Oct. 2013.• <http://Volcanoes.com>• • "Volcano Hazards Program." Volcano Hazards Program. U.S. Department of the

Interior, Oct.-Nov. 2013. Web. 14 Oct. 2013.• <http://en.wikipedia.org/wiki/Volcano>• • Weston, Meg. "Volcano Photos, Information and Stories." Volcano Photos,

Information and Stories. SiteGround, 17 Apr. 2013. Web. 14 Oct. 2013.