EAPS 100 PURDUE EXAM 2 QUESTIONS
WITH 100% CORRECT ANSWERS
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
What is triangulation? - Answer- plot distance from epicenter to three stations
What is the intensity scale? - Answer- defines earthquake size by severity of damage
What is the magnitude scale? - Answer- defines earthquake size by amount of ground
motion measured on seismograph
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 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 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
WITH 100% CORRECT ANSWERS
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
What is triangulation? - Answer- plot distance from epicenter to three stations
What is the intensity scale? - Answer- defines earthquake size by severity of damage
What is the magnitude scale? - Answer- defines earthquake size by amount of ground
motion measured on seismograph
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 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 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
