Download Q: What theory explains why the continents move? Q: What causes

Q: What theory explains why the continents
move?
A: The Continental Drift Theory
Q: What causes the mid-ocean ridges to form?
A: Sea-floor spreading
Q: What is associated with transform boundaries?
A: earthquakes
Q: How do scientists measure tectonic plate
motion?
A: with global positioning systems (GPS)
Q: What is another name for stress squeezing an
object?
A: compression
Q: What is another name for stress pulling an
object?
A: tension
Q: What does the continental drift theory state?
A: The idea that all continents were once part of
one big landmass.
Q: What is it called when Earth’s magnetic poles
change places (north to south and south to north)?
A: magnetic reversal
Q: What can tectonic plates form when they
converge or come together?
A: mountains
Q: What is a fault?
A: the surface of a broken rock layer
Q: What is another name for the bending of a rock
layer?
A: a fold
Q: What is made by earthquakes and was used to
help measure the thickness of the Earth?
A: seismic waves
Q: What is the layer of rock called that the plates
move around on? It is slow flowing solid.
A: asthenosphere
Q: Where is the Earth’s crust?
A: on the outside layer of the Earth
Q: Which layer of the core is liquid iron?
A: the outer core
Q: Which layer of the Earth makes up 67% of the
mass of the Earth?
A: the mantle
Q: What do scientists call the super-continent?
A: Pangaea
Q: What are tectonic plates?
A: pieces of the lithosphere
Q: How is a “normal” fault made?
A: When tension breaks a rock layer.
Q: How is a convergent boundary formed?
A: When tectonic plates move together.
Q: How is a “reverse” fault made?
A: When compression breaks a rock layer.
Q: New crust in the ocean is a sign that what has
happened?
A: sea-floor spreading
Q: How is a “divergent” boundary formed?
A: When tectonic plates move apart.
Q: The lithosphere floats on a layer of the Earth’s
mantle called the _______________.
A: asthenosphere
Q: The mantle mainly consists of a dense layer
called the ___________.
A: mesosphere
Q: The solid layer at the Earth’s center is known
as the _________________________.
A: inner core
Q: The process whereby rock layers are raised to
higher elevations is _______________.
A: uplift
Q: Which is most dense, the mantle or the crust?
Why?
A: The mantle is denser than the crust because it
contains more magnesium.
Q: What is the main element that makes up the
inner and outer cores?
A: iron
Q: Why do seismic waves travel through earth’s
layers at different speeds?
A: It all depends upon the density of the materials
through which the waves are traveling.
Q: What are three bits of evidence that support the
theory of continental drift?
A: 1. similar fossils are found on both sides of the
ocean.
2. similar natural resources are found on both
sides of the ocean.
3. the continents fit together like a puzzle.
Q: What is a rift zone?
A: Sets of deep cracks that form between two
tectonic plates that are pulling away from each
other.
Q: True or False? Evidence for sea-floor
spreading has come from magnetic minerals on
the ocean floor.
A: True
Q: True or False? The further you go away from
the Mid-Atlantic ridge, the younger the rock is.
A: False. The further you go away form the MidAtlantic ridge, the older the rock is.
Q: Is the Atlantic Ocean getting larger?
A: Yes.
Q: If the Atlantic Ocean is getting larger why is
the Earth not growing in size?
A: Rock is being recycled (subduction)
Q: What is “ridge push”?
A: It is when oceanic lithosphere slides downhill
due to gravity.
Q: What is the process of moving layers of rock
by heating and cooling called?
A: convection
Q: What is “slab pull”?
A: When denser oceanic lithosphere sinks beneath
continental lithosphere.
Q: What is an anticline?
A: It is an upward arching rock layer.
Q: What is a syncline?
A: It is a downward arching rock layer.
Q: What kind of fault happens when the hanging
wall moves down relative to the footwall?
A: a normal fault
Q: What kind of fault happens when the hanging
wall moves up relative to the footwall?
A: a reverse fault
Q: What is “subsidence”?
A: It is the sinking of rock layers.
Q: What is “uplift”?
A: It is the rising of rock layers.
Q: What does “litho”, “meso”, and “astheno”
mean?
A: litho = rock; meso = middle, astheno = weak
Q: What kind of force can lead to mountains with
sharp, jagged peaks?
A: tension
Q: What type of boundary is formed when plates
slide past each other?
A: transform boundary
Q: What is used to measure the density of Earth’s
layers?
A: seismograph
Q: Why didn’t Alfred Wegener’s peers accept his
theory of continental drift?
A: Scientists of the time did not know what could
cause large land masses to move. They didn’t
have an answer to the question, “Why?”
Q: What are the layers of the Earth based on their
physical properties?
A: lithosphere, asthenosphere, mesosphere, outer
core, and inner core.
Q: What are the layers of the Earth based on their
compositions?
A: crust (1%), mantle (67%), and core (33%)
Q: What do seismographs measure?
A: They measure the speed and intensity of
earthquakes.
Q: The mantle is composed of more of the element
_____________________ than the crust.
A: magnesium