Chapter 5
Review
Vocabulary
 All of the Earth’s landmasses
were once joined in the
supercontinent __________.
 Pangaea
Vocabulary
 At the mid-ocean ridge, ______
occurs because of the welling up
of molten material from the
mantle.
 Sea-floor spreading
Vocabulary
 A plate boundary where two
plates come together is called a
_________.
 Convergent boundary
Vocabulary
 The process of one plate moving
under another is ______.
 Subduction
Vocabulary
 The theory of _______ states
that the lithosphere of the Earth
is divided into moving pieces.
 Plate tectonics
Vocabulary
 Any plate boundary where the
plates move away from each
other is called a _________.
 Divergent boundary
Vocabulary
 When a plate is subducted, a
deep ocean valley, or ________,
is formed.
 Trench
Vocabulary
 A plate boundary where two
plates slide past each other is a
_________.
 Transform boundary
What’s the Difference?
 Convergent Boundary vs.
Divergent Boundary
 Convergent- when two plates
come together. Divergent- when
two plates move away from each
other.
What’s the Difference?
 Lithosphere vs. Tectonic Plate
 A tectonic plate is one of the
pieces that make up the
lithosphere.
What’s the Difference?
 Subduction zone vs. Trench
 Subduction zone- the place
where one plate is pushed down
under another. Trench- and
ocean valley that forms in a
subduction zone.
Check Your Knowledge
 How did scientists prove that
sea-floor spreading occurs?
 Scientists found a patter of
parallel magnetic stripes in the
sea floor and found that the age
of the crust increases the farther
away you get from the ridge.
Check Your Knowledge
 List the three ways in which
plates can interact with one
another.
 Plates can converge, diverge, or
slide past one another.
Check Your Knowledge
 How do the marks left by ancient
glaciers provide evidence for
continental drift?
 Glaciers always flow toward
oceans, so the marks left in rocks
by a glacier should point toward
an ocean. Some glacial marks do
not point toward present-day
oceans, indicating that the
landmasses were not always
oriented as they are today.
Check Your Knowledge
 Explain the two models proposed
for how convection moves plates.
 One model says that the plates
are simply floating on convection
cells. The other model says that
the plates are actually part of the
convection cells.
Check Your Knowledge
 What landforms can result when
two plates meet at a convergent
boundary?
 Trenches, volcanoes, and
mountain ranges.
Check Your Knowledge
 What is the theory of continental
drift?
 The theory of continental drift
states that the Earth’s
landmasses were once
connected, have moved apart,
and are still moving.
Check Your Knowledge
 How does the age of rocks found
at the bottom of the ocean
compare to the age of rocks
found on the continents?
 Ocean rocks are younger than
rocks from continents.
Check Your Knowledge
 List the three kinds of convergent
boundaries.
 Oceanic-oceanic, oceaniccontinental, and continentalcontinental.
Check Your Knowledge
 What two continents were formed
when Pangaea broke apart?
During which era of geologic time
did this occur?
 Laurasia and Gondwanaland.
Mesozoic Era.
True or False?
 The present-day continents of
Africa, South America, Australia,
India, and Antarctica were once
joined as the continent Laurasia.
 False; Gondwanaland
True or False?
 The mid-ocean ridges are all
subduction boundaries.
 False; divergent
True of False?
 Tectonic plates “float” on the
lithosphere.
 False; asthenosphere
True or False?
 The density of oceanic crust if
greater than the density of
continental crust.
 True
Check Your Understanding
 Where is new crust created?
 Along a divergent boundary.
Check Your Understanding
 How do continental plates differ
from oceanic plates?
 Continental plates include both
continental and oceanic crust.
Check Your Understanding
 What happens to the rock
material of a subducting plate?
 The rock material melts and is
absorbed into the mantle.
Check Your Understanding
 Where do we typically find ocean
trenches?
 Associated with subduction
zones.
Check Your Understanding
 What kind of fault line is the San
Andres Fault?
 A transform boundary
Check Your Understanding
 What is another name for the
Earth’s internal heat?
 Geothermal energy.
Check Your Understanding
 What kind of boundary were the
Himalayan Mountains formed at?
 A convergent boundary.