PRESENTATION BY :

SAKINA

VOLCANOESA volcano is a mountain where lava (hot, liquid rock) comes from a magma chamber under the ground.[1]

Most volcanoes have a volcanic crater at the top. When a volcano is active, materials come out of it. The materials include lava, steam, gaseous sulfur compounds, ash and broken rock pieces.

When there is enough pressure, the volcano erupts. Some volcanic eruptions blow off the top of the volcano. The magma comes out, sometimes quickly and sometimes slowly. Some eruptions come out at a side instead of the top.

Volcanoes are found on planets other than Earth. An example is Olympus Mons on Mars.

Volcanologists are scientists who study volcanoes using methods from geology, chemistry, geography, mineralogy, physics and sociology.

TYPES OF VOLCANOES

Basic types of Volcanoes1. Active Volcanoes2. Dormant Volcanoes1.Sheild Volcanoes2.Strato Volcanoes3.Caldera

ACTIVE VOLCANOES

DORMANT VOLCANOES

SHIELD VOLCANOES

STRATO VOLCANOES

CALDERA

PLACES WHERE WE HAVE ACTIVE VOLCANOES

Avachinsky-Koryaksky in Russia[8]Barren Island in the Andaman and Nicobar Islands of IndiaCerro Azul in Chile[7]Colima in Mexico[8]Chimborazo in EcuadorCotopaxi in Ecuador[7]Galeras in Colombia[8]Glacier Peak in the US (Washington)Haleakala in US (Hawai'i)Irazu in Costa Rica[9]Kelut in Indonesia[10]Kilauea in the US (Hawaii)Krakatoa in Indonesia[10]Lō'ihi Seamount in the US (Hawai'i)[11]Mount Adams in US (Washington)Mount Baker in the US (Washington)[12]Mount Fuji in Japan[13]

Mount Hood in the US (Oregon)[14]Mount Lassen in the US (California)[10]Mount Mayon in Albay in the PhilippinesMount Merapi in Indonesia[15]Mount Olympus in US (Washington)Mount Pinatubo in the Philippines[10]Mount Rainier (Tahoma) in the US (Washington)[16]Mount Slamet in Central Java, IndonesiaMount St Helens in US WashingtonMauna Kea in US (Hawai'i)[17]Mauna Hualalai in US (Hawai`i)Mauna Loa in the US (Hawaii)[17]Nevado del Ruiz in Colombia[10]Pacaya in Guatemala[2]Parícutin in Mexico[7]Popocatepetl in Mexico[7]Redoubt in US (Alaska)[2]Sakurajima in Japan

Sinabung in Indonesia[8]Taal in the Philippines[19]Tambora in Indonesia[10]Ulawun in Papua New Guinea[8]Mount Unzen in Japan[1

Other regions of active volcanoes include the Mediterranean Sea, the Atlantic Ocean and other places.

Sinabung in Indonesia[8]Taal in the Philippines[19]Tambora in Indonesia[10]Ulawun in Papua New Guinea[8]Mount Unzen in Japan[1

PLACES WHERE WE HAVE DORMANT VOLCANOES

TOP 5 DORMANT VOLCANOES :1.Mount Kea , Hawaji.2.Mount Pelee , Martinique.3.Mount Fuji , Japan.4.Mount Ararat , Turkey.5.Mount Kilimanjaro , Tanzania ,

Africa.

VOLCANO IN MOUNT KEA , HAWAJI

MOUNT PELEE , MARTINIQUE

MOUNT FUJI , JAPAN

MOUNT ARARAT , TURKEY

MOUNT KILIMANJARO , TANZANIA , AFRICA

QUESTIONS :

• Lava is the molten rock expelled by a volcano during an eruption.

• The resulting rock after solidification and cooling is also called lava.

• The source of the heat that melts the rock within the earth is geothermal energy.

• When first erupted from a volcanic vent, lava is a liquid usually at temperatures from 700 to 1,200 °C

1. What is Lava?

2. What is Magma?

• Magma is a mixture of molten or semi-molten rock, volatiles and solids that is found beneath the surface of the Earth.

• Besides molten rock, magma may also contain suspended crystals, dissolved gas and sometimes gas bubbles.

• Magma often collects in magma chambers that may feed a volcano or solidify underground to form an intrusion.

• Magma is capable of intruding into adjacent rocks dikes and extrusion onto the surface as lava, and explosive ejection as tephra to form pyroclastic rock.