The Ring of FireA Presentation by Danny Jensen

What is… The Ring of Fire? The Ring of Fire is an arc of volcanic and seismic activity that

is located on the border of the Pacific Plate

What is… The Ring of Fire? (cont.) The Ring of fire is a chain of volcanoes that rings around the

Pacific plate This ring contains 452 volcanoes Nearly 75% of all volcanoes in the world are located on this

ring

Volcanoes… How do they work? Most volcanoes that are formed on land are a direct result of

tectonic plates coming together where one subducts under the other into the mantle. This causes an increase in both temperature and pressure in the

mantle

Volcanoes… How do they work? (cont.)

When both temperature and pressure increase, the rock inside the mantle melts and turns into liquid rock, or magma

Pressure is built up until the magma is forced to release onto the Earth’s surfaceVolcanoes form from multiple releases of magma

on the Earth’s surface

Formation of the Volcano When the magma erupts at the Earth’s surface, it creates

lava flows and ash deposits that layer the volcano’s formation.

Magma starts in the reservoir,

builds its way up the throat as

pressure increases, and finally

erupts through the vent and

flows down the side of the

volcano, creating multiple layers

of ash and magma

The Cascades Range A key feature on this range is Mt. St. Helens

Because of the magma that dwells in subduction zones is very viscous (resistant to flow), eruptions are very violent when they explode.

Earthquakes Another key feature of The Ring of Fire is both minor and

major earthquakes. Earthquakes can occur from three different tectonic plate

activities: Convergent

Occurs at a convergent fault line when two plates collide Divergent

Two plates separate. Magma rises from the mantle to fill the gap or one plate slides down to fill the space.

Transform When two plates rub against each other and slide in opposite

directions.

Earthquake & Volcano Correlation Often, when two plates collide, one of the plates submerges

beneath the other. It is this subduction that creates the temperature and pressure increase that forms magma and volcanoes.

Deep ocean trenches and huge earthquakes are also created along these fault-lines

Formation of other Geologic Landmarks

The Andes Mountains is a direct result of the Ring of Fire’s activities The Andes were created from the Nazca plate being pushed

under the South American Plate.

Recent Activity August 26/27, 1883: The volcano, Krakatoa, in the Indian Ocean

erupts. It kills nearly 40,000 people as tsunami waves crash into Java and Sumatra and are felt as far away as England.

 May 18, 1980: Mount St. Helens in southwest Washington state erupts, killing 57. The eruption was triggered by a 5.1 magnitude earthquake.

June 9, 1991: Mount Pinatubo, 80 km north of Manila, erupts. It kills over 700 and destroys 200,000 buildings.

Bibliography Univ. of Delaware, . N.p.. Retrieved from

http://www.ceoe.udel.edu/extreme2001/geology/ringoffire.html

The New York Times Company. (n.d.). Retrieved from http://geography.about.com/library/faq/blqzringoffire.htm

Svitil, K. (n.d.). Retrieved from http://www.pbs.org/wnet/savageearth/hellscrust/html/sidebar3.html

Unknown. (n.d.). Retrieved from http://www.angelfire.com/sc3/popocatepetl/page2.html

Unknown. (n.d.). Retrieved from http://library.thinkquest.org/03oct/00758/en/disaster/earthquake/tectonics.html