PEO 2 Lecture Cards

Question 1

Which crystallized deeper in the Earth’s crust? Some granite with 4mm quartz crystals or some granite with 6mm quartz crystals?

Answer 1

Granite with 6mm quartz crystals.

Question 2

Volcanic material that is expelled into the air and falls back to Earth is referred to as…

Answer 2

Tephra/Pyroclastics

Question 3

Which of the minerals below crystallizes at the highest temperature? (Na-rich plagioclase feldspar, K feldspar, Ca-rich plagioclase feldspar)

Answer 3

Ca-rich plagioclase feldspar

Question 4

Which volcanic (extrusive) igneous rock type listed below contains the least amount of SiO?

Answer 4

Komatiite

Question 5

What kind of rocks are peridotite and granite?

Answer 5

Plutonic (intrusive) igneous rocks

Question 6

Is plutonic intrusive or extrusive igneous rock?

Answer 6

Intrusive

Question 7

Is volcanic intrusive or extrusive igneous rock?

Answer 7

Extrusive

Question 8

Which volcanic rock type is the most abundant on Earth?

Answer 8

Basalt

Question 9

What is the term used to describe basaltic lava that has a ropy or satiny appearance after it cools?

Answer 9

Pahoehoe

Question 10

What is the correct term of a large conical volcanic mountain that is composed of pyroclastics and occasional basalt lavas?

Answer 10

Stratovolcanoes

Question 11

What type of volcanic mountains are the largest?

Answer 11

Shields

Question 12

Those largest volcanic mountains are composed of what volcanic igneous rock type?

Answer 12

Basalt

Question 13

What type of volcanic event killed volcanologists Maurice and Katia Kraft?

Answer 13

Pyroclastic flow

Question 14

What is a caldera?

Answer 14

It is where a volcano has erupted and then collapsed in on itself, sometimes fills with water.

Question 15

Most volcanic ash consists of what material? (Be precise)

Answer 15

Tiny bits of volcanic glass

Question 16

Which type of volcanic event is the most dangerous, and most likely to result in large loss of life?

Answer 16

Pyroclastic flow

Question 17

What was, by far, the largest historically recorded volcanic eruption?

Answer 17

Tambora

Question 18

Significant amounts of Earth’s heat are transferred via conduction at only 3 locations: (1) within the solid inner core, (2) within the lithosphere, and (3) at the boundary between the _____ and the base of the _____.

Answer 18

Outer core, mantle.

Question 19

Periodotite and komatite are examples of what kind of rock?

Answer 19

Ultramafic

Question 20

Gabbro and basalt are examples of what kind of rock?

Answer 20

Mafic

Question 21

Diorite and andesite are examples of what kind of rock?

Answer 21

Intermediate

Question 22

Granite and rhyolite are examples of what kind of rock?

Answer 22

Felsic

Question 23

What is the first silicate mineral to crystallize in Bowen’s Reaction Series?

Answer 23

Olivine

Question 24

Three types of material are erupted through volcanoes, what kind flows onto the surface?

Answer 24

Lava

Question 25

Three types of material are erupted through volcanoes, what kind is ejected into the air?

Answer 25

Tephra

Question 26

Three types of material are erupted through volcanoes, what kind are gases?

Answer 26

Volatiles

Question 27

All Earthquakes that occur at great depth (100-700 km below Earth's surface) occur at what type of geologic tectonic location?

Answer 27

Subduction Zones

Question 28

In what year did the "great" Charleston earthquake occur?

Answer 28

1886

Question 29

Which type of seismic waves travel at the fastest speeds?

Answer 29

P-waves

Question 30

What do we call the location of Earth's surface directly above where the earthquake started?

Answer 30

The epicenter

Question 31

What is the term used to identify the location where the rupture that causes an earthquake started?

Answer 31

Focus

Question 32

Which country has had the two earthquakes that caused the greatest loss of human life?

Answer 32

China

Question 33

Through which of the rock types listed would seismic P-waves travel at the greatest velocity? (Rhyolite, diorite, andesite, gabbro, granite)

Answer 33

Gabbro

Question 34

The velocity of seismic waves is affected by the nature of the material through which they travel. They will speed up if they ender materials that are _____ or _____.

Answer 34

Denser; rigid

Question 35

Describe the geologic/tectonic locations where the great majority of large/major earthquakes (magnitude >5) occur? (Be specific)

Answer 35

At subduction zones

Question 36

Expulsion of what gas from a volcano killed >1700 people and their cattle in Cameroon in 1984?

Answer 36

CO2

Question 37

What type of seismic information provided the evidence that confirmed that there is a solid core within the liquid core of the Earth?

Answer 37

Nuclear test blasts

Question 38

In the open (deep) ocean how can one identify a tsunami? (Be specific)

Answer 38

Small waves at high speeds

Question 39

What happens to seismic vibrations if they pass through unconsolidated sediment, as compared to the same ones that pass through igneous rock?

Answer 39

The vibrations are amplified; the less rigid a material, the most amplified the vibrations become

Question 40

What does the occurance of, and size of, the S-wave shadow zone

Answer 40

It tells us the size and diameter of the liquid core and that it was a sphere.

Question 41

As a tsunami approaches a shoreline, what happens to its speed and height?

Answer 41

Speed decreases, and height increases

Question 42

Damage to tall buildings is mostly caused by which type of seismic waves? (Be specific)

Answer 42

Low frequency surface waves

Question 43

Data from at last _____ seismographs are necessary to accurately locate the site of an earthquake.

Answer 43

3

Question 44

Which type of seismic waves represent side to side motion (ground shaking) that results in stucco and brick detaching from buildings?

Answer 44

Love waves

Question 45

True or False - There is more total relief on the outer core/mantle boundary than there is on the Earth's surface (top of Mt. Everest to bottom of the Mariana Trench, ~20 km)

Answer 45

True

Question 46

What is the Bouguer gravity anomaly likely to be 1500 km offshore of South Carolina, where the sea floor is ~4500 meters deep? (+250, +160, +70, 0, -50, -130, -250)

Answer 46

+250

Question 47

Recently, some companies have used airborne gravity surveys to looks for what?

Answer 47

Metallic ore (iron, gold, platinum, silver, etc.)

Question 48

Complete the formula for gravitational attraction between two objects. What should be where the ? is? F = G ((m1 x m2)/?)

Answer 48

d^2

Question 49

Explain precisely what the d^2 represents in the formula for gravitational attraction between two objects?

Answer 49

The distance between the center of mass between m1 and m2.

Question 50

Which important geologic principle stipulates that Earth's curst behaves as if it floats on/in denser material beneath it?

Answer 50

Isostasy

Question 51

What major topographic features on Earth are not in isostatic equilibrium, and their Bouguer gravity anomalies do not match the expected values based on their elevation/depth?

Answer 51

Ocean trenches/Deep sea trenches

Question 52

What is the Curie Point?

Answer 52

The temperature at which cooling rocks lock in their magnetic location.

Question 53

An increase of one unit of moment magnitude represents how much increase in the amount of energy released by an earthquake?

Answer 53

31.6x

Question 54

(True or False) The north and south magnetic poles switch positions episodically?

Answer 54

True

Question 55

_____ is the difference, measured as an angle, between the direction to the geographic north pole (true north) and the magnetic pole.

Answer 55

Declination