Science - volcanoes

Volcano parts, volcano types
magma chamber
a reservoir of magma inside the earth; magma collects in a pocket beneath a volcano
openings where ash escapes into the atmosphere; opening at Earth's surface where volcanic materials escape
a long tube that connects the magma chamber to the earth's surface
a depression in the summit of a volcano
a crack in the earth's crust that allows magma to travel through and eventually reach the surface
fragments of volcanic rock and lava that are blasted into the air in large explosions; typically made of rhyolite
lava flow
masses of molten rock that pour onto Earth's surface during an eruption
obsidian rock
shiny, smooth dark volcanic rock
pumice rock
three type of volcanoes
shield, cinder cone, composite
Volcanoes are classified by eruptions. What are the two types of eruptions
quiet, explosive
a crater that is more than 1 km long; an enlarged crater; formed when the summit of the volcano is weak and collapses
pyroclastic flow
any fragments or material released by a volcano
volcanic rock
volcanoes produce lava which hardens into rocks; two examples are pumice and obsidian
Quiet eruptions
Magma low in silica (flows easily, low viscosity), produce Panhoehoe and AA lava; Shield volcano; example is Hawaiin Islands
Explosive eruptions
Has magma high in silica (high viscosity, flows slowly), Magma builds up in the volcanoes pipe and gasses inside the magma build pressure and then expolde, incredible force of eruption;
Composite volcano Cinder Cone
Composite: can have an explosive or quiet eruption, taller than cinder cone volcanoes; has one vent
Cinder Cone: explosive eruption, smallest type of volcano, has one vent
Cinder Cone vs. Shield Volcano
Cinder Cone: smallest type of volcano, has steep sides, explosive eruption
Shield: has multiple vents, has broad gentle slopes
Composite vs. Shield Volcanoes
Composite: has only one vent, formed on convergent boundary, can have explosive or quiet eruption
Shield: has multiple vents, has broad gentle slopes, can form at a hot spot
Example of a Shield Volcano
Island of Hawaii
Example of a Cinder Cone
Sunset Crater, Arizona
Example of a Composite volcano
Mt. St. Helen's in Washington; Mt. Fuji in Japan
smallest most basic type of volcano
molten material below the Earth's surface
lava flow with a rope like texture
an enlarged crater
location of mt st helen's
volcanoes eventually erupt because of a build up in this
cinder cone volcanoes have only one of these
viscosity of magma depends on temperature and
silica content
to decrease the viscosity of a liquid you can increase
volcanoes that will never erupt again
volcanoes that have not erupted for a long period of time, but may erupt again
hot spot
volcano that does not form over a plate boundary
type of volcano with a gentle slope and broad base
type of eruption produced from either cinder cone or composite volcano
these type of volcanoes have one vent
composite and cinder cone
this type of volcano is formed at a convergent boundary
this type of volcano forms over a hot spot
this type of volcano has multiple vents
this type of volcano has both quiet and explosive eruptions

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