VOLCANOES
What is a volcano?
Avolcano isarupture, vent, orfissureon
the crustofaplanetarymassobject,such
asthe Earth, which allowshotlava,
volcanicash,andgasesto escapefroma
magmachamberbelowthe surface.It can
alsobemountainsformedbythe
accumulationofthese eruptiveproducts.
What is a volcano?
Volcanoesarelikehugesafety
valvesthatreleasethepressure
thatbuildsupinsidetheEarth.
What is a volcano?
The wordvolcanoisderived
from“Vulcano,” avolcanic
islandintheAeolianIslandsof
Italy.The nameoriginatesfrom
Vulcan,thegod offireinRoman
mythology.
What is a volcano?
Apersonwhostudiesthe
processesinvolvedinthe
formationanderuptiveactivity
ofvolcanoesiscalleda
volcanologist.
Earth’svolcanoesoccurbecause
theplanet’scrustisbrokeninto17
major,rigidtectonicplatesthatfloat
onahotter,softerlayerinearth’s
mantle.
Volcanoesaregenerallyfound
wheretectonicplatesare
divergingorconverging.
Beneathavolcano,liquidmagma
containingdissolvedgasesrises
throughcracksintheEarth’s
crust.
Astheyerupt,volcanoesspewhuge
cloudsofvolcanicashintothe
atmosphere.Volcanoeruptionshave
knockeddownentireforestsand
triggeredtsunamisandearthquakes.
Thefeaturesofvolcanoesaremuch
morecomplicatedandtheirstructure
andbehaviordependonanumberof
factors.
Somevolcanoeshaveruggedpeaks
formedbylavadomes.
Othershavelandscapefeaturessuch
asmassiveplateaus.
PARTS
OFA
VOLCANO
MagmaChamber
Main Vent
SecondaryVent
SecondaryCone
Crater
AshCloud
Ash
LavaFlow
Layersof
ashandlava
Avolcaniccrater isaroughlycircular
depressioninthegroundcausedby volcanic
activity. Itistypicallyabowl-shaped feature
within whichoccursaventorvents.
Amagmachamber isalargepoolofliquidrock
beneaththesurfaceofthe Earth.
Lava ishot liquidrockthatcomesoutofthe
earth throughavolcano.
Volcanicash isaproductof explosivevolcanic
eruptions.
END

Volcanoes - A Presentation