And Answers
How does magma form
✓✓✓✓~ From partial melting. Magma chambers rise up through the surrounding mantle and
lithosphere.
How do igneous rocks form?
✓✓✓✓~ From magma cooling
What is magma that reaches the surface called
✓✓✓✓~ lava
What is an extrusive igneous rock?
✓✓✓✓~ Rocks that are formed when lava hardens above the Earth's surface. Extrusion can
be explosive or flowing.
What is an intrusive igneous rock?
,✓✓✓✓~ Rocks that are formed when magma hardens beneath Earth's surface. They
harden slowly.
What is a large body of intrusive rock called?
✓✓✓✓~ Pluton
What are extrusive igneous features
✓✓✓✓~ Lava flows, Fissure eruptions, Volcanoes(many different types)
Intrusive Igneous features
✓✓✓✓~ Batholith
laccolith
sills
Dykes
Volcanic Necks
What are the basic volcano types
✓✓✓✓~ Shield Valcano(Hawaii), Cinder cone(nicaragua), Composite cone(mount fiji)
Extrusive igneous bodies
,✓✓✓✓~ Lava, Volcanic tuff(pyroclastic flow), Volcanic ash
Batholith
✓✓✓✓~ A mass of rock formed when a large body of magma cools inside the crust
Laccolith
✓✓✓✓~ A local intrusive body with other rocks below(fed by dykes)
Examples of Batholiths
✓✓✓✓~ Sieraa nevada, Coast range on the west coast
Laccoliths examples
✓✓✓✓~ Devils tower(Wyoming), Mount Royal(montreal)
Torres del paine(chile)
What are magam 3 components
✓✓✓✓~ Melt(the liquid portion composed of mobile ions)
Solids(If any are silicate minerals that have already crystallized from the melt)
, Volatiles(gases dissolved in the melt like H2O, CO2 SO2) violitiles make magma
rise faster and change how it behaves
geothermal gradient
✓✓✓✓~ the gradual increase in temperature with depth in the crust on average 25 degrees
per km
Rocks in the lower crus and upper mantle are between what temperatures
✓✓✓✓~ 1500-2500 degrees
What 3 causes cause melting to beginning
✓✓✓✓~ Confining pressure drops slightly, Temperature increased, volatiles are introduced
What is decompression melting
✓✓✓✓~ melting due to a drop in confining pressure that occurs as rock rises
What is crystallization?
✓✓✓✓~ Cooling magma results in the systematic arrangement of ion into crystal structures.
What is a mantle of composed of peridotite rich of?