Download INSIDE THE EARTH

Inside The Earth Unit Outline
EARTH’S INTERIOR
EQ1: How do geologists study the Earth’s interior? direct evidence – rock samples,
evidence – seismic waves produced from earthquakes
indirect
EQ2: What are the characteristics of each layer of Earth?
 Crust - Ocean floor is made mostly of Basalt and the Continental crust is made mostly of
Granite

Mantle –hot, soft solid (like taffy). The upper part of the mantle is the lithosphere and
connects to the crust. Beneath the lithosphere is the asthenosphere.

Core – made of nickel and iron. The core is divided into two parts – outer core which is
liquid and inner core which is solid due to intense pressure.
EQ3: What causes convection currents in the mantle? Heat from the core is powering the
convection currents. The mantle that is close to the core heats up and rises, mantle that is
away cools down and sinks. This just keeps happening to create a current.
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Seismic waves – vibrations that travel through Earth carrying the energy released during an
earthquake
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Lithosphere – a rigid layer made up of uppermost part of the mantle and the crust
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Asthenosphere – the soft layer of the mantle on which the lithosphere floats
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Convection – the transfer of thermal energy by the movement of a fluid
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Convection current – the movement of a fluid, caused by differences in temperature, that
transfer heat from one part of the fluid to another
DRIFTING CONTINENTS & SEA-FLOOR SPREADING
EQ4: What evidence supports continental drift?
- Land features on multiple continents match-up
(mountains, coal beds)
-
Fossils that were unable to fly or swim are found
in the same area (if the continents are pieced
together)
-
Fossils of tropical plants were found in cold
areas which means that areas once had to have
been closer to the equator in order for the plant
to have grown.
EQ5: What evidence supports sea-floor spreading?
Along the mid-ocean ridge, molten material is coming
to Earth’s surface. Rock samples have proven that
the newest rock is found at the mid-ocean ridge and
the rocks get older as you move further from the
ridge.
EQ6: What happens at deep-ocean trenches? Subduction
occurs at deep-ocean trenches. This is where the sea
floor goes back into the mantle.
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Continental drift – the hypothesis that the continents slowly move across Earth’s surface
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Pangaea – the name of the single landmass that broke apart 200 million years ago and gave
rise to today’s continents
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Fossil – a trace of an ancient organism that has been preserved in rock
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Mid-ocean ridge – an undersea mountain chain where new ocean floor is produced
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Sea-floor spreading – the process by which molten material adds new oceanic crust to the
ocean floor
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Deep-ocean trench – a deep valley along the ocean floor beneath which oceanic crust slowly
sinks toward the mantle
PLATE TECTONICS
EQ7: What is the theory of plate tectonics? Theory that pieces of Earth’s lithosphere are in
constant slow motion driven by convection currents in the mantle.
EQ8: How do the 3 types of plate boundaries move and what major events do they cause?
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Plate - a section of the lithosphere that slowly moves over the asthenosphere, carrying
pieces of continental and oceanic crust
Scientific theory – a well-tested concept that explains a wide range of observations