Earth Science Study Guide
crust
lithosphere
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Outermost layer.
Made of huge slabs of rock that float on the mantle.
Texture: Solid and brittle.
Most abundant elements are oxygen and silicon.
Lithosphere is the layer under the crust.
asthenosphere
mantle
 Layer between the crust and the outer core.
 A solid with plasticity, so that the crust floats on it.
 Asthenosphere is the part of the mantle closest to the
crust.
outer core
 Layer between the mantle and the inner core.
 Liquid.
inner core
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earth's structure
 Outer layers are less dense than inner layers.
 Movement in the asthenosphere and mantle drive plate
movement in the crust because of convection. See
diagram below on the left.
Innermost layer.
Center of the earth.
Sphere of hot, solid metal.
Kept solid by pressure.
Made of iron and nickel.
major plates
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Geologic Events
 Ocean basins are created when oceanic plates diverge
(move apart) and new crust is formed when magma
rises and cools.
 Earthquakes are when movement of the plates or rock
happens so quickly that it sends out vibrations moving
the nearby rock. This mostly happens at transform (side
by side) boundaries.
 Volcanic eruptions occur mostly when one plate is
being subducted beneath another as the two plates
converge(move towards each other.) Melting occurs that
rises to the surface creating the Volcano.
 Mountains are built when plates converge and neither
gives way to the other.
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Rock Cycle
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1.
2.
3.
4.
5.
7.
Pacific Plate.
Eurasian Plate: largest plate.
South American Plate.
African Plate.
North American Plate.
Australian Plate.
Process by which rock is
broken down, formed, and /
or changed into other kinds
of rock.
Rock: formed from minerals.
Three kinds of rock:
o Igneous, Sedimentary.
Metamorphic.
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Igneous Rock
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Sedimentary
Rock
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Metamorphic
Rock
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Formed from melted rock:
o Magma: melted rock
underground.
o Lava: melted rock at
earth's surface.
Likely shows evidence of
volcanoes nearby.
Examples:
o Obsidian.
o Granite.
o Pumice.
o Basalt: forms ocean floor.
Rock formed from sediment
by weathering and erosion.
Sediment: small pieces of
rocks, minerals, or shells.
Formed by:
o Compaction: pressure
from rocks on layers
below.
o Cementation: minerals
form a "glue" that holds
sediments together.
Examples:
o Limestone.
o Sandstone.
Rock changes form, deep
underground (at C in
picture).
Formed by:
o Heat.
o Pressure.
"Morph" means change.
Examples:
o Marble.
o Slate.