Exam 2

Question 1

Layers of the Earth

Answer 1

Inner Core, Outer Core, Crust, Mantle,

Question 2

What is the Inner Core made of?

Answer 2

Iron and Nickel, it is solid.

Question 3

What is the Outer core made of?`

Answer 3

Iron and Nickel but it is liquid

Question 4

What is the Mantle made of?

Answer 4

Silicates

Question 5

What is the substance of the Asthenosphere and what does it enable?

Answer 5

Mainly comprised of liquids and it allows the Lithosphere to float and move up top.

Question 6

What are the two types of Crust?

Answer 6

Continental and Oceanic

Question 7

What is the difference between the Continental and Oceanic crust?

Answer 7

The Continental is granitic, about 3.8 billion years old, 30-50 km
The Oceanic is basaltic, 130 million years old, 5-12 km

Question 8

What is Alfred Wegener remembered for?

Answer 8

Came up with the theory of Continental Drift.

Question 9

What is some evidence that Alfred Wegener had?

Answer 9

shape of continents- continental plates come together at the break of the continental shelf most precisely.
rock structures- distinct rocks on both sides of ocean. however not accepted.
fossils- mesosaurs, cynognathus, lystrosaurus, and glossopteris on all southern continents with no mechanism to transport across ocean.
paleoclimate (glaciers)-evidence of extreme changes in climate compared to today. coal deposits in antarctica. evidence from:evaporites, eolian deposits, coral reefs.

Question 10

Who came up with the theory of Sea Spreading?

Answer 10

Harry Hess

Question 11

What are the sea floor features?

Answer 11

Shelf- broad shallow layer, less than 500 meters deep, home to fisheries, snorkling, etc. Along the shoreline
Slope: The slope at the end of a continental shelf that leads down to the deep ocean floor.
Rise: The sloping sea floor that extends from the lower part of the continental slope to the abyssal plain.
Mid-ocean ridge: A 2km high submarine mt. belt that forms along a divergent oceanic plate boundary.
Abyssal plain: Broad relatively flat regions of the ocean that lie at a depth at about 4-5 km below sea level.
Trench: A deep longate trail bordering a volcanic arc. A trench defines the trace of a convergent plate boundary (Subduction zone)
Paleomagnetism: The record of ancient magnetism preserved in rock.

Question 12

What is the Divergent effect, motion, topography, and volcanic activity?

Answer 12

Effect: Constructive (Oceanic lithosphere created)
Motion: Spreading
Topography: Ridge/Rift
Volcanic activity: Yes

Question 13

What is the Convergent effect, motion, topography, and volcanic activity?

Answer 13

Effect: Destructive (Oceanic Lithosphere destroyed)
Motion: Subduction
Topography: Trench
Volcanic Activity: Yes

Question 14

What is the Transform effect, motion, topography, and volcanic activity?

Answer 14

Effect: None
Motion: Lateral Sliding
Topography: No Major effect
Volcanic Activity: no

Question 15

What are three types of Convergent?

Answer 15

Oceanic-Oceanic (Island Arc) ex. Japan
Oceanic-Continental (Volcanic Arc) ex. Cascade Ridge
Continent-Continent (Suture Zone)

Question 16

What is an Earthquake? (Elastic Rebound Theory)

Answer 16

vibration of the Earth cause by rupture and sudden movement of rocks that have been strained beyond their elastic limit.

Question 17

What is the Focus of an Earthquake?

Answer 17

Focus = Precise underground spot at which rocks begin to rupture or shift

Question 18

What is the Epicenter of an Earthquake?

Answer 18

Epicenter = Point on surface of earth directly above the focus

Question 19

What are the two kinds of Seismic Waves?

Answer 19

Surface Waves

Body Waves: P waves (P for Primary) S waves (S for Secondary)

Question 20

What are the characteristics of Surface waves?

Answer 20

They have a side-to-side displacement as well as an up and down motion.

Question 21

What are the characteristics of P waves?

Answer 21

P Waves (primary waves)
Travel through solids and liquids
Velocities of 5-15 km/second
Compressional waves

Question 22

What are the characteristics of S waves?

Answer 22

S Waves (secondary waves)
Travel through solids only
Velocities of 3-8 km/second
Transverse (shear) waves

Question 23

Characteristics of the Richter Scale

Answer 23

Measures the amplitude of seismograph readings
Each point on the Richter scale represents a factor of 10 difference in seismograph intensity
Factor of 30 difference in actual energy released

Question 24

What are the description and magnitudes of an Earthquake on the Richter Scale?

Answer 24

Great		8 or higher	1
Major		7–7.9		18
Destructive	6–6.9		120
Moderate        5–5.9		800
Light		4–4.9		6,200
Minor		3–3.9		49,000
Very minor	2–3			300,000

Question 25

How can you calculate the epicenter of an Earthquake?

Answer 25

If we know how fast P and S waves travel through the crust, and we know the time difference between the arrival of the P and S waves at a particular seismic station, we can calculate how far away the focus is from the station.

Question 26

How many seismic stations do you need to calculate the focus of an earthquake and why?

Answer 26

You need 3 seismic stations to locate, or triangulate, the focus of an earthquake, because even if you know how far away it is, you don’t know the direction.

Question 27

What do Earthquakes cause?

Answer 27

1. Ground displacement 2. Ground motion 3. Ground failure - landslide - liquifaction 4. Fire 5. Tsunamis

Question 28

Where is the discontinuity of the Moho and the Guttenberg?

Answer 28

moho: base of crust Guttenberg: base of mantle

Question 29

What is Deformation?

Answer 29

When a rock is subjected to increasing stress.

Question 30

What are the three stages of deformation?

Answer 30

Elastic Deformation: the strain is reversible Think of a rubber band. Ductile Deformation: the strain is irreversible. Fracture: irreversible strain, the material breaks. Stress (shear, compressional, tensional)

Question 31

What are the different types of stress response?

Answer 31

Brittle: brittle rocks tend to fracture when placed under a high enough stress. Brittle materials have a small or large region of elastic behavior but only a small region of ductile Elastic: For small differential stresses, less than the yield strength, rock deforms like a spring. It changes shape by a very small amount in response to the stress, but the deformation is not permanent. If the stress could be reversed the rock would return to its original shape. Plastic: is the ability of a rock layer to bend without breaking

Question 32

What is lava?

Answer 32

Magma that reaches the | Earth’s surface.

Question 33

What is magma?

Answer 33

A body of molten rock found at depth, including any dissolved gases and crystals.

Question 34

What is a Caldera?

Answer 34

A large depression created by the collapse of a volcano

Question 35

What is a Cinder Cone?

Answer 35

A simple volcano created from blobs of lava ejected from a single vent.

Question 36

What is a shield cone?

Answer 36

Created by countless outpourings of fluid lava flows.

Question 37

What is a stratovolcano?

Answer 37

Built of layers of lava, ash, and volcanic debris

Question 38

What is a lava dome?

Answer 38

mound formed when viscous lava piles up around a vent

Question 39

What are pyroclasts?

Answer 39

Fragments blown out by explosive volcanic eruptions and subsequently deposited on ground. Include ash, cinders, lapilli, blocks, bombs, and pumice.

Question 40

what is deformation?

Answer 40

When rock or rocks of bodies are subjected to stresses beyond their own strength they change shape mainly through folding and faulting.

Question 41

What is stress?

Answer 41

Stress: Force applied to a material that tends to change its dimensions or volume; force per unit area.

Question 42

What is strain?

Answer 42

Strain: The change in shape or orientation that results from applying stress to a rock body.

Question 43

What are the responses (styles of deformation)?

Answer 43

``` 1.Elastic: rocks deform by flowing; until stress is removed. 2. Plastic: rocks deform by flowing; they remain deformed after stress is removed. 3. Brittle: rocks deform by breaking. ```