When a fault is expressed at the
surface, it is called a __________.
fault scarp
The name of the site where slippage
begins and earthquake waves radiate
outward is called the __________.
hypocenter
If the stress applied to the rock is
greater than rock strength, what
happens?
Blocks of rock will slide relative to one
another along a fault, causing an
earthquake.
The hanging wall moves __________
relative to the footwall in a __________
fault.
down; normal
Which of the following is a
characteristic of an S wave?
"shaking" particle motion at right
angles to the direction of wave travel
Which of the following might be seen
where strike-slip movement has
occurred?
offset fences
What best describes the movement of
P waves?
compression and expansion
Amongst all seismic waves, surface
waves __________.
have the slowest velocity
The names primary and secondary
refer to ___________.
wave speed
Define earthquake intensity.
A qualitative measure of the amount
of ground shaking at a certain
location.
A smaller earthquake in Virginia was
felt over a larger distance, as
compared to a larger earthquake in
California. What is a reason this
occurred?
colder crust
Richter magnitude (ML) is derived
from measuring __________ and
__________, and then plotting them on
a Richter diagram.
S minus P wave time; maximum S
wave height
Why is moment magnitude (MW)
preferred over Richter magnitude
(ML)?
Moment magnitude measures the
total energy released during an
earthquake and can adequately
measure the energy of large
earthquakes.
Which of the following best describes
liquefaction?
the transformation of stable soil into
loose, liquefied material that is able to
rise toward Earth's surface
Describe how sand volcanoes form.
An earthquake causes loose,
saturated sandy material to liquefy,
shoot upward through fractures of a
confining unit, and eventually erupt at
the surface.
__________ in the sandy layer causes
the ground to subside after sand
volcanoes form.
Tighter packing
Structures built on __________ will
become unstable during an
earthquake.
loose, saturated sediments
A tsunami is caused by __________.
anything that displaces water
A __________ is located at a plate
boundary between a subducting slab
of oceanic crust and an overlying
plate.
megathrust fault
What happens to tsunami waves as
they move closer to shore?
Velocity decreases and height
increases.
Which of the following locations on
the Circum-Pacific Belt are likely to
generate a tsunami?
west coast of South America
__________ is a seismic zone that has
not produced a large earthquake for a
considerable length of time.
A seismic gap