ANSWERS
Which U.S. region is made up of a series of high-angle normal faults producing nearly
parallel mountain ranges? - Answer- basin and range province
Which of the following is a real-world example of isostatic adjustment? - Answer-
rebound of the landmass around Hudson Bay after glacial ice sheets have retreated
Why would geologic mapping be difficult in an area dominated by accreted terranes? -
Answer- each terrane is geologically distinct, but also highly deformed
________ is the downslope movement of rock, regolith, or soil under the direct influence
of gravity. - Answer- mass wasting
What term is commonly used to describe a sudden event in which large volumes of rock
move down steep slopes? - Answer- rockslide
Which of the following locations would be most likely to see large-scale, rapid mass
wasting? - Answer- The Rocky Mountains
Which of the following factors does not influence mass wasting? - Answer- geologic age
Stream valleys are produced through combined effects of mass wasting and running
water. If running water alone were responsible for creating stream valleys, how would
they appear? - Answer- V-shaped valleys
Which region would be most likely to produce a catastrophic landslide? - Answer- steep,
geologically young mountains
What is the controlling force of mass wasting? - Answer- gravity
A ________ is not the sole cause of a mass wasting event, but the last of many causes
that initiate the downslope movement of materials. - Answer- trigger
Which of the following scenarios would lead to a mass wasting event due to an over
steepened slope? - Answer- heavy rain saturate slope materials
What is the angle of repose? - Answer- the steepest angle at which a material remains
at rest
, Which sediment size has the steepest angle of repose? - Answer- gravel
A stream is flowing over a hill covered in thick soil. The stream is eventually blocked to
create a small pond in order to free land downhill for construction. What will ultimately
happen to the strength and cohesion of the soil in the area around this pond? - Answer-
strength and cohesion will decrease
Which physical property was responsible for determining how Earth materials separate
into interior layers at the time of Earth's formation? - Answer- density
What is a mineral phase change? - Answer- Atoms in a mineral are rearranged into a
denser and more stable structure.
________ is the process where materials separate into different layers due to density. -
Answer- differentiation
What is the major difference between the inner core and the outer core? - Answer- The
inner core is solid while the outer core is liquid.
What is the primary method scientists use to determine the layering of the interior of the
Earth? - Answer- seismic waves
What will happen to a seismic wave when it is reflected? - Answer- The wave will be
bounced back toward its source.
What will happen to a seismic wave when it is refracted? - Answer- The wave will be
bent when passing into a material of differing density.
Which seismic waves would be most useful in determining the extent and thickness of
the Earth's interior layers? - Answer- P & S waves
Which of the following materials will allow for the fastest transmission of seismic waves?
- Answer- rigid, less compressible material
What is diffraction? - Answer- A seismic wave is bent when it passes by a curved
surface.
Why do seismic waves follow strongly curved paths as they move through the interior? -
Answer- Their velocities are changed because of increasing pressure with depth.
A relatively weak layer in the Earth due to temperature is known as the ________. -
Answer- asthenosphere
Where is the thinnest continental crust in North America? - Answer- basin and range
region