EAPS 100 PURDUE - EXAM 2
QUESTIONS AND ANSWERS 100%
CORRECT
What causes earthquakes? - ANSWER-rapid release of energy and slip along fault
which causes rock movement
What are the 3 types of faults? - ANSWER-normal, reverse, strike-slip
What is a fault? - ANSWER-A break in the earth's crust
What is a footwall block? - ANSWER-block below the fault
What is a hanging wall block? - ANSWER-block above the fault
How are faults formed? - ANSWER-when tectonic forces add stress to rock
What are the three types of stress? - ANSWER-compression, tension, shear
Compression Stress - ANSWER-squeezes rocks together till it folds or break, causes
shortening, convergent boundary
What is tension stress? - ANSWER-stress that pulls a material apart, causes
lengthening, divergent boundary
What is shear stress? - ANSWER-causes one sides to slide past the other, transform
boundary
What is elastic deformation? - ANSWER-The concept that an elastic material will return
to its original shape when the force is removed
What is a normal fault? - ANSWER-hanging wall moves down relative to footwall,
results from tensional stress (example: continental rift)
What is a seismic belt? - ANSWER-A region of earthquake activity
Where are divergent boundary earthquakes? - ANSWER-Mid-ocean ridges:
-along the spreading ridge, normal faults
-along active transform boundaries, strike-slip faults
(shallow-focus earthquakes)
, Where are transform boundary earthquakes? - ANSWER-Strike slip faults generate
earthquakes
Ocean: cut through mid-ocean ridges
Continent: San Andreas Fault, Alpine Fault
Shallow-focus earthquakes: large ones cause disasters
San Andreas Fault - ANSWER-1200 km long, continental transform fault
What is a reverse fault? - ANSWER-hanging wall moves up relative to the footwall,
results from compression (example: mountain belts)
What is a thrust fault? - ANSWER-reverse fault with a low angle slope
What is a strike-slip fault? - ANSWER-when one block slides laterally past the other
block with no vertical motion across the fault (faults are vertical, motion is horizontal)
What is the focus of an earthquake? - ANSWER-the location where seismic waves first
begin, point where slip initiates, seismic energy radiates from it
Where does the focus lie? - ANSWER-Continental crust: 5 and 20 km depth
Oceanic lithosphere: Benioff zone (660 km)
Shallow-focus earthquakes: top 60 km
Intermediate-focus earthquakes: 60 to 300 km
Deep-focus earthquakes: 300 to 660 km
What is the epicenter of an earthquake? - ANSWER-the point on Earth's surface directly
above the focus, represents the position of an earthquake on a map
What is a body wave? - ANSWER-a wave moving on the interior of the earth
What is a surface wave? - ANSWER-a wave moving on the surface of the earth, most
destructive, slower than body waves
What is a convergent boundary earthquake? - ANSWER-have shallow, intermediate,
and deep earthquakes, shallow earthquakes occur on both plates and along contact
What happens during convergent boundary earthquakes? - ANSWER-large thrust faults
along the contact, normal faults form where slab bends, almost all the larges
earthquakes on record are here
Where do convergent boundary earthquakes occur? - ANSWER-Intermediate-focus and
deep-focus earthquakes: in downgoing slab defining Wadati-Benioff zone
Plate Boundary Earthquakes - ANSWER-Shallow: divergent, transform, convergent
boundaries
Intermediate and deep: convergent boundaries
QUESTIONS AND ANSWERS 100%
CORRECT
What causes earthquakes? - ANSWER-rapid release of energy and slip along fault
which causes rock movement
What are the 3 types of faults? - ANSWER-normal, reverse, strike-slip
What is a fault? - ANSWER-A break in the earth's crust
What is a footwall block? - ANSWER-block below the fault
What is a hanging wall block? - ANSWER-block above the fault
How are faults formed? - ANSWER-when tectonic forces add stress to rock
What are the three types of stress? - ANSWER-compression, tension, shear
Compression Stress - ANSWER-squeezes rocks together till it folds or break, causes
shortening, convergent boundary
What is tension stress? - ANSWER-stress that pulls a material apart, causes
lengthening, divergent boundary
What is shear stress? - ANSWER-causes one sides to slide past the other, transform
boundary
What is elastic deformation? - ANSWER-The concept that an elastic material will return
to its original shape when the force is removed
What is a normal fault? - ANSWER-hanging wall moves down relative to footwall,
results from tensional stress (example: continental rift)
What is a seismic belt? - ANSWER-A region of earthquake activity
Where are divergent boundary earthquakes? - ANSWER-Mid-ocean ridges:
-along the spreading ridge, normal faults
-along active transform boundaries, strike-slip faults
(shallow-focus earthquakes)
, Where are transform boundary earthquakes? - ANSWER-Strike slip faults generate
earthquakes
Ocean: cut through mid-ocean ridges
Continent: San Andreas Fault, Alpine Fault
Shallow-focus earthquakes: large ones cause disasters
San Andreas Fault - ANSWER-1200 km long, continental transform fault
What is a reverse fault? - ANSWER-hanging wall moves up relative to the footwall,
results from compression (example: mountain belts)
What is a thrust fault? - ANSWER-reverse fault with a low angle slope
What is a strike-slip fault? - ANSWER-when one block slides laterally past the other
block with no vertical motion across the fault (faults are vertical, motion is horizontal)
What is the focus of an earthquake? - ANSWER-the location where seismic waves first
begin, point where slip initiates, seismic energy radiates from it
Where does the focus lie? - ANSWER-Continental crust: 5 and 20 km depth
Oceanic lithosphere: Benioff zone (660 km)
Shallow-focus earthquakes: top 60 km
Intermediate-focus earthquakes: 60 to 300 km
Deep-focus earthquakes: 300 to 660 km
What is the epicenter of an earthquake? - ANSWER-the point on Earth's surface directly
above the focus, represents the position of an earthquake on a map
What is a body wave? - ANSWER-a wave moving on the interior of the earth
What is a surface wave? - ANSWER-a wave moving on the surface of the earth, most
destructive, slower than body waves
What is a convergent boundary earthquake? - ANSWER-have shallow, intermediate,
and deep earthquakes, shallow earthquakes occur on both plates and along contact
What happens during convergent boundary earthquakes? - ANSWER-large thrust faults
along the contact, normal faults form where slab bends, almost all the larges
earthquakes on record are here
Where do convergent boundary earthquakes occur? - ANSWER-Intermediate-focus and
deep-focus earthquakes: in downgoing slab defining Wadati-Benioff zone
Plate Boundary Earthquakes - ANSWER-Shallow: divergent, transform, convergent
boundaries
Intermediate and deep: convergent boundaries
