Seismology and Faults

Question 1

what are seismographs?

Answer 1

instruments used to detect and record earthquake vibrations

Question 2

seismographs are instruments used to ____ and _____ earthquake vibrations

Answer 2

detect, record

Question 3

what do seismographs detect and record?

Answer 3

earthquake vibrations

Question 4

The reports you get from a seismograph is called…

Answer 4

a seismogram

Question 5

Modern seismographs use sensitive _____ and _____

Answer 5

optics, electronics

Question 6

a seismograph measures…

Answer 6

the earth’s vibrations in two different directions

Question 7

How many directions does a seismograph measure the earth’s vibrations?

Answer 7

two

Question 8

what are the two directions measured by a seismograph?

Answer 8

• the horizontal movement of the Earth - Vertical Earth movement

Question 9

Energy in earthquakes travels outward as _____

Answer 9

waves

Question 10

What is the name of the originating point where a tectonic slip occurs?

Answer 10

the focus

Question 11

Earthquake ______ emit outwards from the focus

Answer 11

waves

Question 12

What are the two broad categories of earthquake waves?

Answer 12

1. Surface waves 2. Body waves

Question 13

Where do surface waves travel?

Answer 13

along the earth’s surface

Question 14

What are the three characteristics of surface waves?

Answer 14

• travel along earth’s surface - very destructive - are the last to reach the seismograph (slowest)

Question 15

Where do body waves travel?

Answer 15

Through the Earth’s interior

Question 16

What are the two types of body waves?

Answer 16

• P waves - S waves

Question 17

P waves are _______ waves

Answer 17

compressional

Question 18

P waves can travel through….

Answer 18

solids, liquids, and gases

Question 19

When P waves are emitted they travel in ______ directions including deep into the Earth

Answer 19

all

Question 20

S waves can travel through…

Answer 20

any solid

Question 21

the wave motion of S-waves is…

Answer 21

perpendicular to travel direction

Question 22

What are s-waves called?

Answer 22

shear waves

Question 23

are s-waves faster or slower then p-waves?

Answer 23

slower

Question 24

How is the distance to the epicenter figured out?

Answer 24

• from the seismogram
• by using the arrival times of seismic waves

Question 25

Which release more energy, earthquakes or volcanoes?

Answer 25

earthquakes

Question 26

In order for a rock to break it has to have ______ and ______ on it.

Answer 26

stress and strain

Question 27

What is stress?

Answer 27

the force acting on a surface, per unit area

Question 28

Stress can be a force that is squezzing, which is called ________ or it can be a force that is pulling a rock apart, which is called \_\_\_\_\_\_\_, or it can be a force that is sliding past a a rock, which is called \_\_\_\_\_\_

Answer 28

compression, tension, shear

Question 29

Compression is a force that is...

Answer 29

squezzing the rock

Question 30

Tensional force is a force that is...

Answer 30

pulling a rock apart

Question 31

Shear is a force that is...

Answer 31

sliding past a rock

Question 32

What is strain?

Answer 32

a rocks response to stress

Question 33

What are some rock repsones to stress?

Answer 33

it either breaks, squishes, or stretches out, or it changes shape in some other way

Question 34

As a result of stress and strain, what happens?

Answer 34

rock deformation

Question 35

What is elastic deformation?

Answer 35

when a rock bends but does not break and once the stress it removed the rock snaps back to its original shape

Question 36

Which type of deformation do we most commonly see in earthquake situations?

Answer 36

elastic

Question 37

What is ductile deformation?

Answer 37

when rocks flow or bend but do not break, and do not snap back to their original shapd once the stress is removed

Question 38

In ductile deformation, does the rock snap back to its original shape?

Answer 38

no

Question 39

What is brittle deformation?

Answer 39

when rocks crack or break

Question 40

when rocks crack or break this is called....

Answer 40

brittle deformation

Question 41

when a rock bends but does not break and once the stress it removed the rock snaps back to its original shape this is called...

Answer 41

elastic deformation

Question 42

What are the three types of deformation?

Answer 42

elastic, ductile, and brittle

Question 43

what are the types of stress?

Answer 43

tension, compression, and shear

Question 44

What are faults?

Answer 44

fractures in the earths crust along which movement is occuring and where we see a lot of stress

Question 45

What are plate margins?

Answer 45

gigantic faults

Question 46

why are there faults that occur throughout the earth's crust?

Answer 46

becuase the earth's crust is constantly undergoing stress

Question 47

What are the four types of faults?

Answer 47

- normal - reverse - thrust - transform

Question 48

A normal fault forms as a result of...

Answer 48

tensional stress

Question 49

a reverse fault form as a result of, and in response to...

Answer 49

compressional stress

Question 50

a thrust fault forms in response to...

Answer 50

compressional stress

Question 51

the angle of a thrust fault is...

Answer 51

closer to horizantal

Question 52

a transform fault forms in response to...

Answer 52

shear stress

Question 53

a divergent plate boundary is equivalent to which type of fault?

Answer 53

normal

Question 54

a convergent plate boundary is equivalent to which type of fault?

Answer 54

reverse/thrust

Question 55

a transform plate boundary is equivalent to which type of fault?

Answer 55

transform