the world of volcanoes mrs. lozano. what is a volcano? a mountain formed by lava and ash
TRANSCRIPT
The World of Volcanoes
Mrs. Lozano
What is a volcano?
• A mountain formed by lava and ash
What is Lava?• Lava is magma that reaches
Earth’s surface
• Okay...I know what lava is, but what exactly is Magma?
• Magma is hot, soft rock from Earth’s mantle.
What is ash?• Ash is small pieces of hardened
lava
How do volcanoes form?• Continental plates and oceanic
plates collide• Subduction occurs• Melted rock becomes magma that
forces its way up between the plates
• Savage Earth Animation #2
How do volcanoes form?
Where are these “Subduction Zones?”
• Many volcanoes are located at plate boundaries around the Pacific plate.
• The Pacific plate is often called the “Ring of Fire”
Do all volcanoes look the same?• No, there are many different kinds
of volcanoes such as:• Shield Volcanoes that can be
found in Hawaii
• Cinder Cone Volcanoes can be found in Costa Rica
• And Fissure Volcanoes found in Nicaragua .
Do subduction zones create all volcanoes?• No, volcanoes can also be formed
by Hot Spots.• Hot Spots are volcanic areas on
the surface of the Earth that are created by a rising plume of magma.
• http://www.classzone.com/books/earth_science/terc/content/investigations/es0810/es0810page03.cfm
Volcanic Hazards • Volcanoes can create landslides
that bury land, homes and sometimes people.
Volcanic Hazards• Volcanoes can create Earthquakes
that may produce hazards which include ground cracks, ground deformation, and damage to manmade structures.
Volcanic Hazards• Pyroclastic Surge that spews
extremely hot ash that races down the mountain and swallows everything in its path.
Volcanic Hazards• Lava flows are the most famous
yet the least dangerous of hazards.
Volcanic Hazards• There are two kinds of lava flows:
– Pahoehoe
– `A`A
I love Volcanoes!!!!!!• Although volcanoes are beautiful
and wondrous things, they can be harmful and cause many disasters. It is better to love volcanoes from a far off distance.