EEPS 108 Midterm 1
In magma, ________ is the most abundant dissolved gas. A) water vapor (H2O) B) carbon dioxide (CO2) C) sulfur dioxide (SO2) D) hydrogen sulfide (H2S) E) carbon monoxide (CO)
A) water vapor (H2O)
The Houston-Galveston, Texas, area has been sinking due to the ________. A) withdrawal of groundwater by pumping B) dissolution of limestones C) emptying of a magma chamber D) weight of all the high-rise buildings and houses E) dissolution of a salt layer
A) withdrawal of groundwater by pumping
37) A tall office building built on a foundation designed to slide or roll with an earthquake is an example of using ________ to reduce earthquake-induced damage. A) bracing B) base isolation C) buttressing D) resonance E) framing
B) base isolation
A moving, glowing cloud of hot gases and volcanic pieces: A) was named with a Hawaiian term because it's so common there. B) is called a pyroclastic flow. C) is so rare, none occurred last century. D) is associated with shield volcanoes.
B) is called a pyroclastic flow.
Granite A) is an extrusive igneous rock. B) is felsic in composition. C) logically could be found in a lava flow D) is the coarse-grained equivalent of andesite
B) is felsic in composition.
6) The presence of water ________ the melting point of rock. A) raises B) lowers C) does not change D) may raise or may lower
B) lowers
22) The New Madrid earthquakes are apparently related to an old buried ________. A) transform fault B) rift zone C) subduction zone D) hazardous waste dump E) oil pipeline
B) rift zone
12) The trees that died in the Pacific Northwest after the great earthquake of 1700 were killed by ________. A) mass wasting events in the days after the earthquake B) seawater after a tsunami rushed onshore C) a cloud of methane that was released from sediments during the shaking D) seawater after the land dropped below sea level E) the liquefaction of their underlying soils
B) seawater after a tsunami rushed onshore
Which of Earth's layers accounts for most of the volume of Earth? A) the inner core B) the mantle C) the lithosphere D) the crust
B) the mantle
33) The frequency of a wave is ________. A) the amount of displacement of the medium through which the wave is passing B) the number of waves passing a given point per unit time C) the time between successive waves D) the energy of the wave
B) the number of waves passing a given point per unit time
1) What properties of magma determine whether an eruption is relatively peaceful or explosive?
Viscosity and amount of dissolved gas If low viscosity, the dissolved gas escapes easily. If high viscosity (usually higher SiO2 content), tend to be more explosive and contain more dissolved gas/volatiles.
4) Explain which factors contribute to seismic wave amplitude from earthquakes and how.
Waves change amplitude and velocity depending on what kind of rock they are travelling through. In hard rock, velocity is higher and amplitude is lower. In softer rock/soil, velocity is slower but amplitude is higher.
Explain how physical and chemical weathering work together to form sediments.
Work together to: Increase surface area (physical). Dissolve minerals and cements (chemical). Alter hard minerals into soft minerals (chemical).
Which statement is TRUE? a. Raleigh and Love waves are surface seismic waves. b. S-waves are compressional body waves; P-waves are shear body waves. c. Surface waves are the first to show up on a seismogram recording of a quake. d. Shallow-focus quakes do less damage than deep-focus quakes.
a. Raleigh and Love waves are surface seismic waves.
Aftershocks are smaller than the main shock in an earthquake sequence. a. True b. False
a. True
At depths below 100 km, subduction zone earthquakes occur almost exclusively in the interior of the subducting oceanic lithosphere. a. True b. False
a. True
P and S waves do not follow simple paths as they pass through Earth; they speed up, slow down, and change direction, and S waves even disappear when they reach Earth's core. a. True b. False
a. True
To describe the location in three-dimensional space of a deformed rock layer or a fault surface, geologists make measurements known as dip and strike. a. True b. False
a. True
Continental mountain ranges such as the Alps, Himalayas, and Appalachians are the result of which of the following? a. continent-continent convergent plate boundaries b. divergent plate boundaries c. subduction plate boundaries d. hot spots
a. continent-continent convergent plate boundaries
Earth's magnetic field is created by: a. flow of liquid iron in Earth's molten outer core. b. centrifugal force pushing on Earth's crust. c. convecting iron-rich silicates in Earth's mantle. d. the rotation of the planet on its axis.
a. flow of liquid iron in Earth's molten outer core.
Asthenosphere: a. is warm enough to flow slowly. b. subducts when it collides with continental lithosphere. c. is the lower layer of both continental and oceanic lithosphere. d. is the uppermost layer of Earth's core.
a. is warm enough to flow slowly.
Which of the following is NOT a mineral? a. oil, because it's a liquid, not a solid b. halite, because it's not crystalline c. a gold nugget, because it's a native metal d. pyrite, because it's a chemical compound
a. oil, because it's a liquid, not a solid
Which of the following lists the most abundant elements in rocks found at the Earth's crust and in the mantle? a. oxygen and silicon b. iron and aluminum c. hydrogen and helium d. calcium and carbon
a. oxygen and silicon
Accretionary prisms form due to what process? a. subduction b. divergence c. rifting d. transform motion
a. subduction
Earthquakes but not volcanoes occur in San Francisco because: a. two plates are moving past each other (approximately parallel) there. b. a continental plate is colliding with another continental plate there. c. an oceanic plate is converging with a continental plate and subducting there. d. two plates are diverging there.
a. two plates are moving past each other (approximately parallel) there.
Plate tectonics theory was widely accepted by scientists in what decade? a.1920s b.1960s c.1980s d.1930s
b. 1960s
Radiometric dating of a magnetic anomaly stripe of rock that is 225 km away from the mid-ocean ridge axis gives an age of 4.5 million years. Assuming a constant rate, sea-floor spreading in this area occurs at a rate of: a. 50 km per year. b. 1,012.5 km per year. c. 5 cm per year. d. 20,000 cm per year.
c. 5 cm per year.
List and define the 3 types of rocks.
1) Igneous: Solidified molten rock 2) Metamorphic: Solid state alteration of existing rock 3) Sedimentary: Cementation of grains weathered from other rock or precipitate from a solution
What are the 7 common types of minerals defined in class? Where relevant, provide the anion building block for the mineral type.
1) Silicates: (Most common on Earth (SiO4)^-4 tetdrahedra anion 2) Carbonates: carbonate anion building block (CO3^2- ), e.g., calcite (CaCO3), dolomite 3) Sulfides: S^2- or S2^2- anion, e.g., pyrite (FeS2) (fools gold) 4) Oxides: O^2- anion, e.g., ice (H2O), magnetite (Fe3O4) 5) Halides: halide anion (F-, Cl-, Br-, I-), e.g., halite (NaCl) 6) Phosphates: PO4^3- anions, e.g., apatite 7) Native Elements: e.g., Cu, C, Pb, Ag, S
What are the 4 criteria that define a mineral?
1) They have a definite chemical composition. 2) They have a crystalline structure. 3) They are formed by geologic processes except in unique cases where living organisms can create them. 4) They are a solid.
What are the different factors that control soil formation and how?
1. Climate and vegetation (rain, vegetation adds or removes soil) 2. Substrate composition (Mineral composition, Resistance to weathering) 3. Slope steepness and wetness. Regolith easily washes from steeper slopes. Wetter soils contain more organic material. Flat soils tend to hold more moisture and develop thicker soils. 4. Time: Soils require time to develop. Younger soils tend to be thinner.
1. List the five lines of evidence Wegener used to support the theory of Continental Drift. Explain why this theory was not widely accepted during his lifetime.
1. Fit of the continents 2. Glaciations 3. Fossils of species separated by oceans 4. Climate belts 5. Matching geological markers (mountains, etc) He couldn't explain how the continents moved
What are the 5 ways minerals form?
1. Solidification from a melt 2. Solid-state diffusion 3. Precipitation from a solution 4. Precipitating directly from a gas 5. Biomineralization
3) What are the four controls on melt composition?
1. Source rock --> either mantle or crust 2. Partial melting 3. Assimilation --> how much melt assimilates mantle chamber 4. Magma mixing
Define natural hazard and natural disaster and give an example of each.
A natural disaster is a naturally occurring event that causes harm to land/property and life; Examples: Hurricane Katrina, the Haiti earthquake of 2010 etc. A natural hazard is a naturally occurring phenomenon that causes harm to land/property and life and may occur whether or not one has occurred recently; Examples: earthquakes, hurricanes, flood, mass movement, extreme temperatures, drought, wildfire, tropical storm, extratropical storm, convective storm, local storm, tsunami, volcanic activity
17) The destructive power of a tsunami is due mostly to the great height of the wave. A) True B) False
A) False
The most peaceful eruptions are ________ eruptions. A) Icelandic type B) Plinian C) Strombolian D) Vulcanian E) Surtseyan
A) Icelandic type
What was the origin of the gas that killed 1,700 people in Cameroon in 1996? A) It leaked upward from a volcano-fed lake. B) It flowed down the side of an erupting volcano. C) It was released from a geyser in a nearby national park. D) It was released in a lateral blast of a cinder cone. E) It was formed when acid rain fell on volcanic soils.
A) It leaked upward from a volcano-fed lake.
2) In silicates, silicon and oxygen link up to form the silicon-oxygen ________. A) dihedron B) trihedron C) tetrahedron D) hexahedron E) dodecahedron
C) tetrahedron
Identify the TRUE statement. A) Soil consists of sediment that has been modified over time to produce a material that can support vegetation. B) The accumulation of decaying organic material near the top of a soil is called subsoil. C) The region within a soil where water leaves behind clay and dissolved ions is called the zone of leaching. D) A vertical sequence of various soil layers is called a soil horizon.
A) Soil consists of sediment that has been modified over time to produce a material that can support vegetation.
7) ________ are steep-sided, symmetrical volcanic peaks built of alternating layers of pyroclastic debris capped by high-viscosity andesitic to rhyolitic lava flows that solidify to form protective caps. A) Stratovolcanoes B) Scoria cones C) Shield volcanoes D) Calderas
A) Stratovolcanoes
Identify the TRUE statement. A) The composition of the giant (Jovian) planets is mainly gas and "ice." B) The Sun accounts for almost 50% of the Solar System's mass. C) The only two planets with moons are Earth and Jupiter. D) Our Sun is the only star we know of that has planets associated with it.
A) The composition of the giant (Jovian) planets is mainly gas and "ice."
Which of the following statements about the crust is FALSE? A) The crust is the top of the mantle that has cooled and hardened. B) The upper portion of the crust contains microscopic pores that contain groundwater. C) The crust plus the upper part of the mantle make up the lithosphere. D) There are two different types of crust: oceanic and continental.
A) The crust is the top of the mantle that has cooled and hardened.
18) Tsunami have long wavelengths and very short wave heights in the open ocean. A) True B) False
A) True
23) Aftershocks of the 1811-12 New Madrid, Missouri, earthquakes are still occurring today. A) True B) False
A) True
24) Pumping fluids into Earth has been found to sometimes trigger small earthquakes (magnitudes < 5). A) True B) False
A) True
25) For magnitudes above about 6, the bigger earthquake magnitude means that more people in a larger area and for a longer time will experience the intense shaking. A) True B) False
A) True
27) The largest moment magnitudes measured to date are from earthquakes that occurred in subduction zones. A) True B) False
A) True
29) The types of rock or sediment on which a structure's foundation sits are of paramount importance with respect to whether the structure will be damaged by shaking from an earthquake. A) True B) False
A) True
30) High-frequency P and S waves will have their vibrations amplified by short buildings. A) True B) False
A) True
31) Low-frequency surface waves will be amplified in tall buildings with low frequencies of vibration. A) True B) False
A) True
32) Where the frequencies of seismic waves match the natural vibration frequencies of local geology and buildings, destruction may be great. A) True B) False
A) True
In general, there is an inverse correlation between the frequency and the magnitude of a disaster process. A) True B) False
A) True
The volume of soil does not stay constant but instead swells and shrinks. A) True B) False
A) True
3) The 2004 Indian Ocean tsunami was generated by a magnitude 9.2 earthquake along ________ off the shore of Sumatra. A) a subduction zone B) a seafloor spreading center C) an oceanic transform fault D) a continental rift zone E) a hot-spot island chain
A) a subduction zone
Pyroclastic debris is ________. A) chucks of magma and rocks blown into the air by gas in a volcanic eruption B) solid pieces of rock contained within, and transported by, lava C) the SiO2-poor magma that remains as gas escapes lava as it flows D) the SiO2-rich magma that flows quickly down the side of a volcano
A) chucks of magma and rocks blown into the air by gas in a volcanic eruption
18) Intrusive igneous rocks A) cool slowly and are coarse-grained B) are fine-grained because they cooled slowly. C) are never seen by humans because they form deep in the Earth and are never exposed at the surface. D) are rocks like basalt, andesite, and rhyolite.
A) cool slowly and are coarse-grained
Which type of disasters was the most expensive for the insurance industry for the period 1960-2009? A) hurricanes B) earthquakes C) floods D) winter storms
A) hurricanes
The earliest nebulae to form in the Universe were made almost entirely of: A) hydrogen and helium. B) chlorine and argon. C) iron and magnesium. D) carbon and nitrogen.
A) hydrogen and helium.
35) Earthquake-induced ground motions cause buildings to sway at certain periods. In general, the taller the structure, the ________ the period. A) longer B) shorter C) period does not depend on building height
A) longer
The geothermal gradient: A) refers to the rate of change in temperature with depth in the Earth. B) increases as you go deeper into the Earth. C) averages about 5°C per km in the upper crust. D) states that temperatures near the mantle-core boundary may exceed the temperature of the Sun (5,500°C).
A) refers to the rate of change in temperature with depth in the Earth.
15) The theoretical velocity of a tsunami in the deep ocean is calculated by taking the square root of the product of ________. A) the acceleration due to gravity and the depth of the ocean B) magnitude of the earthquake and the density of the seawater C) wavelength and 1.25 D) wave height and wind speed E) depth of the thermocline and water temperature
A) the acceleration due to gravity and the depth of the ocean
Our Moon: A) was formed by the collision of Earth with a Mars-sized protoplanet. B) was a separate small planet before it was captured by Earth's gravity. C) spun off the fast-spinning Earth during the early formation of the solar system. D) coalesced from gas and dust in its current place next to Earth.
A) was formed by the collision of Earth with a Mars-sized protoplanet.
2. Explain how magnetic anomalies were used to support the concept of sea floor spreading. Specifically, what data was collected? How was it interpreted?
Along with length & age of a chron (a stripe on the seafloor where magnetic polarity is the same), magnetic pole reversals help us determine how fast the sea floor was spreading & prove that it does as well. Collected using a magnetometer, ships passing across the seafloor basalt are able to detect magnetic anomaly strips indicating switches between negative/positive polarity. Paleomagnetism also reflects the direction of Earth's dipole when the igneous rock formed.
Explain elastic rebound theory and how it explains earthquake cycles.
As rocks on opposite sides of a fault are subjected to force and shift, they accumulate energy and slowly deform until their inter- nal strength is exceeded. At that time, a sudden movement occurs along the fault, releasing the accumulated energy, and the rocks snap back to their original undeformed shape. The deformation builds at the rate of a few centimeters per year, over a time period of many years. When the accumulated strain is great enough to overcome the strength of the rocks, an earthquake occurs. During the earthquake, the portions of the rock around the fault that were locked and had not moved 'spring' back, relieving the displacement in a few seconds that the plates moved over the entire interseismic period (D1 and D2 in Time 3). The time period between Time 1 and Time 2 could be months to hundreds of years, while the change from Time 2 to Time 3 is seconds. Like an elastic band, the more the rocks are strained the more elastic energy is stored and the greater potential for an event. The stored energy is released during the rupture partly as heat, partly in damaging the rock, and partly as elastic waves.
11) Tsunami are typically about ________ high in the open ocean, and on average 6 to 15 m high on reaching shallow water. A) 100 m B) 1 m C) 5 m D) 20 m E) 30 m
B) 1 m
19) It is virtually impossible for small ships at sea to survive a passing tsunami. A) True B) False
B) False
28) The acceleration due to gravity is 9.8 meters per second squared (32 feet per second squared), which is referred to as 1.0 g and is used as a comparative unit of measure. Earthquake accelerations have never been measured in excess of 1.0 g. A) True B) False
B) False
At oceanic spreading centers, magmas are rhyolitic in composition. A) True B) False
B) False
Creep is an ultra-slow, almost imperceptible upslope movement of the soil and lower bedrock zones. A) True B) False
B) False
If a particular disaster has a high frequency of occurrence, it also has a large recurrence interval. A) True B) False
B) False
The Volcanic Explosivity Index (VEI) ranges from 1 to 100. A) True B) False
B) False
The higher the viscosity of magma, the more fluid is its behavior. A) True B) False
B) False
The highest temperatures and highest SiO2 contents are in basaltic magma, giving it the lowest viscosity and easiest fluid flow. A) True B) False
B) False
13) The largest historic tsunami wave run-up ever recorded was caused by a massive rockfall into the water at ________. A) Kilauea, Hawaii B) Lituya Bay, Alaska C) Crescent City, California D) Arica, Chile E) Gibraltar
B) Lituya Bay, Alaska
39) ________ occurs when a building's period matches period of passing seismic waves. A) Interference B) Resonance C) Bracing D) Base isolation E) Liquefaction
B) Resonance
21) Which state listed below is most likely to have a magnitude 9 or larger earthquake in the next several hundred years? A) Florida B) Washington C) Texas D) Wisconsin E) South Carolina
B) Washington
Which of the following statements is FALSE? Classification of mass movement events is based on the: A) type of material involved (rock, regolith, snow, and ice). B) age of the material involved (historic, thousands of years old, or millions of years old). C) velocity of the movement (fast, intermediate, or slow). D) environment (subaerial or submarine).
B) age of the material involved (historic, thousands of years old, or millions of years old).
8) The captain of a ship tells you that he once experienced a huge tsunami while sailing in the Pacific Ocean several hundred miles from any landmass. You decide that this sounds a little far-fetched because ________. A) tsunami usually occur only in the Indian Ocean and Caribbean Sea B) tsunami are rarely felt in deep water because they have long wavelengths and low heights C) the ship could not have survived passing through a major tsunami in the open ocean D) earthquakes do not occur in deep ocean waters E) the captain did not describe any tremors or shaking associated with an earthquake
B) tsunami are rarely felt in deep water because they have long wavelengths and low heights
Which of the following statements is false? Volatiles that come out of the Earth as volcanic products A) were dissolved in the molten rock and released as the surrounding pressure lessened. B) usually consist of 50% sulfur dioxide. C) include water, carbon dioxide, nitrogen, hydrogen, and sulfur dioxide. D) contributed to forming Earth's atmosphere and oceans.
B) usually consist of 50% sulfur dioxide.
5) Explain why basaltic lava tends to form the greatest lava flow hazards (as opposed to intermediate or felsic lava)
Basaltic lava has low viscosity and can flow really fast and really far, covering houses/property and suffocating living animals and humans.
Define the two types of body waves and two type of surface waves in terms of particle motion. List the order in which they will appear on a seismogram.
Body waves: P-Waves: P waves cause the ground to compress and expand, that is, to move back and forth, in the direction of travel. P waves can travel through solids, liquids, and even gases. S-Waves: waves shake the ground in a shearing, or crosswise, motion that is perpendicular to the direction of travel. These are the shake waves that move the ground up and down or from side to side. S waves can travel only through solid materials. Surface waves: Love waves: waves that have a horizontal motion that moves the surface from side to side perpendicular to the direction the wave is traveling. Faster than Raleigh waves. Rayleigh waves: waves that cause the ground to shake in an elliptical pattern. This motion is similar to that observed in ocean waves. Of all the seismic waves, Rayleigh waves spread out the most, giving them a long duration on seismograph recordings. Order: P-Waves, S-Waves, Love Waves, Rayleigh Waves
10) Most tsunami travel at speeds of approximately ________ km per hour in the open ocean. A) 0.01 B) 10 C) 1000 D) 0.1 E) 10,000
C) 1000
1) Approximately ________ of Earth's magma extruded through volcanism takes place at the oceanic spreading centers. A) 90% B) 80% C) 70% D) 60% E) 50%
C) 70%
The volcanic explosivity index (VEI) measures size of volcanic eruptions on a scale of 0 to __ ?. A) 1 B) 5 C) 8 D) 10 E) 100
C) 8
20) Which of the following states has the highest earthquake risk? A) Michigan B) Wisconsin C) Arkansas D) North Dakota E) Florida
C) Arkansas
1) The 2004 ________ Ocean tsunami killed an estimated 245,000 people in 13 countries. A) Atlantic B) Pacific C) Indian D) Southern E) Arctic
C) Indian
________ eruptions are the most violent types of explosive eruptions. A) Icelandic-type B) Vulcanian-type C) Plinian-type D) Hawaiian-type E) Pompeiian-type
C) Plinian-type
The heavier elements on Earth (those with atomic numbers greater than 5): A) were in existence at the moment of the Big Bang. B) were formed immediately after the Big Bang. C) are formed by stellar nucleosynthesis during the life cycles of existing stars. D) are constantly being created by fusion in our Sun and blown here by the solar wind.
C) are formed by stellar nucleosynthesis during the life cycles of existing stars.
Boundaries between Earth's layers: A) are noted by the changing metal content of each layer. B) are defined by abrupt changes in earthquake density. C) are places where there is an abrupt change in the density of rock. D) occur because of tides.
C) are places where there is an abrupt change in the density of rock.
14) Tsunami events at a coastline ________. A) always begin with a retreat of the sea B) always begin with a rising of the sea C) can start with a drawdown or rising of the sea D) are always preceded by a large rogue wave
C) can start with a drawdown or rising of the sea
Which is not a tectonic setting for igneous activity? A) hot spot B) continental rifts C) continental transform fault zones D) volcanic arcs bordering ocean trenches
C) continental transform fault zones
After reclassification in 2005, Pluto is no longer classified as a planet because it: A) does not orbit a star. B) is not spherical. C) has not cleared its orbit of other matter.
C) has not cleared its orbit of other matter.
Which of the following chemical weathering reactions breaks down feldspars, such as orthoclase, into clay minerals like kaolinite? A) hydration B) dissolution C) hydrolysis D) oxidation
C) hydrolysis
8) Most rifting occurs at spreading centers ________. A) in the interior of continents B) and subduction zones C) located below sea level D) on the margins of continents E) and hot spots
C) located below sea level
Of the following types of mass movements, which can move fastest? A) creep B) roots C) rock fall D) mudflow E) earth flow
C) rock fall
34) Usually, the biggest concern in designing buildings to withstand large earthquakes is the ________ components of movement. A) upward push from the vertical B) downward pull from the vertical C) sideways push from the horizontal
C) sideways push from the horizontal
Which of the following did not add to the gases that formed Earth's earliest atmosphere? A) volcanic eruptions B) comet collisions C) solar wind D) planetary outgassing
C) solar wind
6) Earthquake-related tsunami are created by sub sea fault movements with pronounced vertical offsets of the seafloor. Such movements occur most commonly along ________. A) oceanic transform faults B) seafloor spreading centers C) subduction zones D) continental rift zones E) hot-spot island chains
C) subduction zones
9) Tsunami wavelengths are on the order of ________ in the open ocean. A) 0.1 m B) 10 m C) 100 m D) 100 km E) 10,000 km
D) 100 km
Analysis of global sites of magma extrusion found that hot spots, such as Hawaii, represent ________ of the total magma extrusion. A) 73% B) 15% C) 80% D) 12%
D) 12%
3) The typical trend in a rising plume of subduction-zone magma is to increase the ________. A) percentage of SiO2 B) viscosity C) explosive potential of the magma by holding in the gases more tightly D) All of these choices are correct.
D) All of these choices are correct.
4) The viscosity of magma is lowered by ________. A) increasing temperature B) increasing volatile content C) decreasing SiO2 content D) All of these choices are correct.
D) All of these choices are correct.
Which soil layer consists of weathered bedrock material that has not yet been leached or had significant accumulation? A) A B) B C) E D) C
D) C
Jupiter, Saturn, and Neptune are: A) terrestrial planets. B) planetesimals. C) rocky planets. D) Jovian planets.
D) Jovian planets.
38) Which of the following is not a way to improve a building's resistance to earthquakes? A) Brace it. B) Bolt it. C) Bracket it. D) Match its period to seismic waves at that location. E) Move most of the weight to the lower floors.
D) Match its period to seismic waves at that location.
36) The intensity of an earthquake is influenced by all but which of the following? A) Earthquake magnitude B) Distance from the hypocenter/epicenter C) Type of rock or sediment making up the ground surface D) The current air pressure E) Duration of shaking
D) The current air pressure
Which of the following disasters has the highest probability of causing a "10-fatality event" each year? A) an earthquake B) a volcanic eruption C) a hurricane D) a tornado E) a flood
D) a tornado
Which of the following statements is false? Igneous rocks A) form from the cooling and crystallization of either lava or magma B) form in great quantity along the mid-ocean ridge. C) were the first rocks to exist on Earth. D) are coarse-grained if they cool extrusively.
D) are coarse-grained if they cool extrusively.
The recurrence interval of a disaster is the average number of years ________. A) before survivors return to their homes B) before the economy returns to pre-disaster levels C) required to exponentially decay to zero D) between same-sized events E) between events of the same type, regardless of size
D) between same-sized events
What process most logically explains the different tilts of gravestones in a hillside cemetery? A) slump B) liquefaction C) mudflow D) creep
D) creep
Magmas have a variety of chemical compositions because of all of the following except A) they come from a variety of source rocks. B) the rocks that melt to make magma are composed of many minerals, not all of which melt under the same conditions. C) the magmas' heat can melt rock from the walls of the magma chamber D) different magmas formed in different locations are isolated and don't mix.
D) different magmas formed in different locations are isolated and don't mix.
4) Tsunami is a Japanese word that means ________ waves. A) big B) killer C) dragon D) harbor E) island
D) harbor
5) Tsunami are created by big "splashes" made in the deep ocean by all but which of the following? A) fault movements B) volcanic eruptions C) landslides D) hurricanes E) meteor impacts
D) hurricanes
Which of the following groups of elements make up the most mass of the whole Earth? A) magnesium, iron, carbon dioxide, and argon B) nitrogen, oxygen, helium, and carbon dioxide C) silicon, iron, potassium, and sodium D) iron, oxygen, silicon, and magnesium
D) iron, oxygen, silicon, and magnesium
Natural cracks in rock that form due to exhumation are called: A) faults. B) salt wedges. C) clasts. D) joints.
D) joints.
7) Tsunami typically have ________ relative to wind-blown waves. A) short periods and short wavelengths B) short periods and long wavelengths C) long periods and short wavelengths D) long periods and long wavelengths E) long periods and no measurable wavelength
D) long periods and long wavelengths
Slides with a spoon-shaped (concave upward) surface are called: A) creep. B) debris flows. C) avalanches. D) slumps.
D) slumps.
Earth's magnetic field is generated in: A) the crust. B) the upper mantle. C) the inner core. D) the outer core.
D) the outer core.
Identify the FALSE statement. Differentiation of large planetesimals and protoplanets: A) is the process by which these bodies develop internal layering. B) began with heating up component materials within these bodies. C) was caused by heat created by the transformation of kinetic energy from collisions into thermal energy. D) was inhibited by the presence of radioactive elements because their decay absorbs heat from the surroundings.
D) was inhibited by the presence of radioactive elements because their decay absorbs heat from the surroundings.
2) Most of the 245,000 deaths from the 2004 Indian Ocean tsunami occurred in ________. A) Thailand B) Sri Lanka C) India D) Bangladesh E) Indonesia
E) Indonesia
16) Which of the following statements is about tsunami in the deep ocean? A) They never "feel" the bottom. B) They only "feel" the bottom if it is less than 4,000 meters deep. C) They only "feel" the bottom if it is less than 3,000 meters deep D) They only "feel" the bottom if it is less than 5,000 meters deep. E) They are always "feeling" the bottom.
E) They are always "feeling" the bottom.
Which of the following disasters has the highest probability of causing a "1,000-fatality event" each year? A) an earthquake B) a volcanic eruption C) a flood D) a tornado E) a hurricane
E) a hurricane
9) If all of the following rocks were to completely melt and reach the same final temperature, which would produce magma with highest viscosity? A) basalt B) gabbro C) andesite D) diorite E) rhyolite
E) rhyolite
3) Explain why the largest earthquakes in the world occur along subduction plate boundaries.
Earthquake magnitude is related to size and area of the slip and subduction zones form the longest, deepest/widest faults. Transform faults usually only occur deepest at 15km whereas subduction faults often go 30km+
Explain which types of natural disasters tend to result in large single-event losses and which tend to result only in small single-event losses. Over time, which types of disasters tend to result in the greatest cumulative losses?
Earthquakes and hurricanes tend to result in large single-event losses and floods and tornados tend to result only in small single-event losses. Over time, weather and climate-related events result in the greater cumulative losses.
Love waves and Rayleigh waves
Love: 10000 miles/hr, side to side motion Rayleigh:7800mikes/hr, up and down motion, reverse an ocean waves so particles moving back
Present the equations for seismic moment (M0) and the moment magnitude scale (MW) and define the variables that go into the equations. An increase in MW of 2.0 corresponds to an increase in M0 by a factor of what?
Moment, M0 (energy units, Joules)M0 = Area*Slip*StiffnessMoment MagnitudeMW = 2/3 log10(M0)-10.7
4) Why do hotspots beneath oceanic lithosphere tend to result in less explosive volcanoes than those beneath continental lithosphere?
Oceanic lithosphere is mafic and continental is more felsic; mafic means lava containing less SiO2 & less volatiles
S and P waves
P: primary wave, compression wave, solids and liquids S: secondary wave, shear wave, can only move through solids
Sketch and label two cross section through the Earth illustrating the layers associated with composition and strength distinctions. Label the approximate depths of each layer.
See slide 21, 22 and 25 on slide deck two (couldn't upload a pic)
2) What factors control the viscosity of magma and how?
Silica content --> higher means higher viscosity Temperature --> higher means lower viscosity Volatiles --> more volatiles means lower viscosity, but more felsic lava has higher viscosity and can contain more volatiles
Explain the Gutenberg-Richter law.
That there is a relationship between magnitide and frequency of earthquakes in a given region and time period; the increase of magnitide of 3.0 and greater earthquakes indicates a greater possibility of having a 4.0 or greater event in the future (for every 10 magnitude 2.0 earthquakes we have we can expect a magnitude 3.0 earthquake. For every 100 magnitide 2.0 earthquakes we have we can expect 10 magnitide 3.0 earthquakes and one magnitude 4.0 earthquake)
What is the 'Big Bang Theory' and what evidence did Hubble use to support this theory?
The 'Big Bang Theory' explains that the universe was formed from a big explosion that happened billions of years ago (about 13.7 billion years ago). After the explosion, the universe began to cool and expand. As a result, atomic particles are produced. Eventually, stars and galaxies began to form too. The pieces of evidence that supported the BBT includes the moving glazes, wherein the farther the galaxy to us, the faster it moves away from us; and the present of the cosmic background radiation, which is the leftover energy from the big bang explosion.
2) In general, there is a lot more earthquake preparedness for slip along the San Andreas in California than in the Pacific Northwest. What are the factors that have contributed to the difference
There has not been an Earthquake in Pacific NW for a long time - not ever in written history. Earthquakes are always on Californians' mind. It's hard to get people to think an earthquake is a threat when it's never happened in US history before. In addition, land is sparse in Pacific NW so a lot of buildings are old and don't even have AC.
What are the three types of submarine mass wasting types and what are their defining characteristics?
Three types, based on degree of disintegration • Submarine slumps: semicoherent blocks break and slip • Submarine debris flows: sediment moves as a slurry • Turbidity currents: sediment moves as a turbulent cloud May be extremely large
Identify the FALSE statement. a. Positive magnetic anomalies occur over areas of sea floor when the poles of Earth's magnetic field and the paleopoles preserved in the sea-floor basalt agree; negative anomalies occur when they are opposite each other. b. All polarity chrons are the same length of time; they differ only in the magnetic strengths they represent. c. The series of rock stripes parallel to and bilaterally symmetrical across the mid-ocean ridge record the sequence of Earth's magnetic reversals over time. d. The width of each rock stripe is a measure of how long the polar direction remained constant.
b. All polarity chrons are the same length of time; they differ only in the magnetic strengths they represent.
Following the paths of P and S waves from Earth's surface inward, there is an initial increase in wave speed but then a marked slowing occurs at a depth of about 100 meters; this defines the top of the lithosphere. a. True b. False
b. False
Normal faulting occurs when the hanging wall moves upward relative to the footwall. a. True b. False
b. False
The biggest earthquake ever recorded instrumentally occurred on 22 May 1960 in southern Chile with a seismic moment magnitude of 9.8. a. True b. False
b. False
The biggest shaking event is called "the earthquake," the smaller ones before it are known as foreshocks, and the smaller ones after it are called aftershocks. a. True b. False
b. False
The point where a fault first ruptures underground is known as the epicenter. a. True b. False
b. False
Which of the following is NOT a characteristic of a rock? a. It is a coherent mass. b. It has a definable chemical composition. c. It is a naturally occurring material. d. It is a collection of minerals or a body of glass.
b. It has a definable chemical composition.
Which of the following statements is FALSE? a. Ocean basins get wider as a result of sea-floor spreading. b. Ocean floor is created by the process of subduction. c. To keep Earth's surface area constant, the amount of sea-floor spreading must equal the amount of subduction. d. Subduction causes continents to move together; sea-floor spreading moves them apart.
b. Ocean floor is created by the process of subduction.
The Himalayas are growing because: a. two plates are moving past each other there. b. a continental plate is colliding with another continental plate there. c. an oceanic plate is converging with a continental plate and subducting there. d. two plates are diverging there.
b. a continental plate is colliding with another continental plate there.
Which of the following is a mineral? a. amber (tree sap) b. oyster shell (CaCO3) c. sugar (formula C6H12O6) d. glass
b. oyster shell (CaCO3)
Continents: a. plow their way through the sea floor. b. passively ride along as the sea floor spreads. c. may subduct if they are old and dense enough. d. have retained the same size and shape throughout Earth's history.
b. passively ride along as the sea floor spreads.
Which of the following was NOT a line of evidence used by Wegener to develop this theory that continents drift? a. the distribution of fossil species b. the presence of earthquakes in seismic belts along trenches, ridges, and fracture zones c. the matching fit of the outline of some of the continents d. matching mountain chains on continents currently separated by oceans
b. the presence of earthquakes in seismic belts along trenches, ridges, and fracture zones
The global occurrence of earthquakes reveals that: a. their locations are randomly scattered. b. they usually occur on the boundaries of plates or at hot spots. c. they usually occur at the center of plates. d. they prove that Earth is splitting apart (rifting) at all plate boundaries.
b. they usually occur on the boundaries of plates or at hot spots.
The global occurrence of earthquakes reveals that: a. their locations are randomly scattered. b. they usually occur on the boundaries of plates. c. they usually occur at the center of plates. d. they prove that Earth is splitting apart (rifting) at all plate boundaries.
b. they usually occur on the boundaries of plates.
4. Graphite is: a. the polymorph of galena. b. harder than glass. c. pure silicon. d. the "lead" in the pencil you write with.
d. the "lead" in the pencil you write with.
Which of the following statements about lithosphere and asthenosphere is TRUE? a. Lithosphere and asthenosphere have the same physical properties; they are both rigid. b. Lithosphere is denser than asthenosphere. c. Lithosphere consists of the crust and the upper mantle, and behaves like a hard layer that breaks and bends. d. Asthenosphere consists of the lower, middle, and upper mantle, and is defined as mantle material that is cooler than 1280°C.
c. Lithosphere consists of the crust and the upper mantle, and behaves like a hard layer that breaks and bends.
Which statement is TRUE? a. P, S, Love, and Raleigh are all body waves that pass through the Earth's interior. b. The hypocenter (focus) is the point on Earth's surface directly above the epicenter. c. Love waves travel faster than Raleigh waves d. S-waves travel twice as fast as P-waves.
c. Love waves travel faster than Raleigh waves
Plate tectonics theory took decades to be accepted because: a. most of Wegener's ideas turned out to be wrong. b. of pure stubbornness by the scientific community. c. Wegener couldn't explain how continents moved. d. climate, fossil distributions, and land shape offered conflicting evidence.
c. Wegener couldn't explain how continents moved.
Identify the FALSE statement. According to present plate tectonics theory: a. plates move on the asthenosphere. b. plates move at speeds of a few centimeters per year. c. a continental plate will subduct under an oceanic plate when the two converge. d. plates are composed of the crust and the uppermost part of the mantle.
c. a continental plate will subduct under an oceanic plate when the two converge.
Which of the following statements is FALSE? Crystals: a. have an orderly internal arrangement of atoms arranged in a lattice pattern. b. grow outward from a seed. c. are formed by the high-temperature, extremely rapid process known as solid-state diffusion. d. display symmetry.
c. are formed by the high-temperature, extremely rapid process known as solid-state diffusion.
A continuous, uninterrupted piece of a single mineral that grows in place is called a: a. grain. b. fragment. c. crystal. d. clast.
c. crystal.
Identify the FALSE statement. Plate movement is influenced by: a. mantle convection, which creates shear at the base of plates. b. slab pull, in which the down going oceanic plate exerts a pull on the rest of the plate. c. mantle plumes, which are created when hot rock rises up from the deep mantle and creates melting at the base of the lithosphere. d. ridge push, in which the elevated rocks at the ridge axis push on rocks farther from the ridge.
c. mantle plumes, which are created when hot rock rises up from the deep mantle and creates melting at the base of the lithosphere.
Short Answer: Explain the differences between convergent, divergent, and transform plate boundaries and list the major types of hazards associated with each. Give an example of each type of boundary.
convergent: continent & continent meet or oceanic & oceanic plate/lithosphere meet or ocean & continent - convergent boundary or subduction zone (EARTHQUAKES, VOLCANOES, TSUNAMIS, LANDSLIDES - Himalayas, Cascades) divergent: mid-ocean ridge, sea-floor spreading, occur in oceanic and continental lithosphere, magma rises from Earth's mantle and forms oceanic lithosphere, explains continents drifting apart (EARTHQUAKES, VOLCANOES - East African Rift) transform: two plates run almost parallel to each other (EARTHQUAKES - San Andreas Fault)
Three basic classes of collisions include all but which of the following? a. Oceanic plate versus oceanic plate b. Oceanic plate versus continent-bearing plate c. Continental plate versus continental plate d. Continental plate versus mantle plate
d. Continental plate versus mantle plate
The slide-past motions of strike slip faults occur in all but which of the following? a. The North Anatolian fault in Turkey b. Along the San Andreas Fault in California with its famous earthquakes c. At the southwestern edge of the Pacific Ocean where the Alpine fault cuts across the South Island of New Zealand d. Where the Indian subcontinent touches Asia
d. Where the Indian subcontinent touches Asia
The genetic scheme for classifying rocks is based on: a. mineral (and therefore elemental) composition. b. temperature and pressure. c. the average grain size. d. origin of formation.
d. origin of formation.
Which statement is TRUE? Earthquakes in California are: a. the result of reverse faulting along the San Andreas Fault. b. the result of widening along the San Andreas Fault, which will eventually cause western California to sink into the ocean. c. always above magnitude 7.5 because the San Andreas is such a large fault. d. shallow and occur in the upper 15 km of crust.
d. shallow and occur in the upper 15 km of crust.
types of dip-slip faults
normal, reverse, thrust
Short Answer: Describe how some of the features of ocean-ocean, ocean-continent, and continent-continent convergent tectonic plate boundaries are different and list the major types of hazards associated with each. Provide an example of each type of convergent boundary
ocean-ocean: Mariana's Trench, ocean plate subducts under the less dense, forms island arcs and volcanoes ocean-continent: Cascades, ocean plate subducts under continental, forms earthquakes and volcanoes and landslides & continental arcs continent-continent: Himalayas, a continental plate is colliding with another continental plate there, forms earthquakes
1) The article 'The Really Big One' is focused on the Cascadia subduction zone in the Pacific Northwest of the United States. Please describe (as if you were talking to a person who is not an Earth Scientist) the geologic context for Cascadia. What kind of fault is it and why is it there?
subduction (oceanic plate under continental plate), Juan de Fuca plate is a small plate between Pacific and North American and is slowly being consumed/taken up by the North American plate. Plates are what our Earth's surface is made up of, constantly shifting to where our continents are today