GSCI 1070 Final Exam: Prep Quiz Questions

Which of the following statements is true with respect to earthquake magnitude and/or earthquake intensity? 1. A magnitude 6 earthquake releases about twice as much energy and results in roughly twice as much ground motion as a magnitude 5 earthquake. 2. Magnitude is a measure of the ground shaking that results from an earthquake, whereas intensity is a measure of the total energy released. 3. Magnitude and intensity are both objective measures of an earthquake's size and power, and are measured directly using scientific instruments. 4. An earthquake's magnitude is only a single number, whereas intensity typically varies depending on how close a location is to the source of earthquake shaking.

an earthquake's magnitude is only a single number, whereas intensity typically varies depending on how close a location is to the source of earthquake shaking 1, 2, and 3 are FALSE

Describes the process by which a magma may become more silica-rich owing to the melting of rocks surrounding the magma.

assimilation

Why is the oldest continental crust (3.8 billion years) so much older than the oldest oceanic crust (200 million years)?

because continental crust does not subduct

As sediment is transported farther away from its source, it becomes...

better sorted and more rounded

Lithification of sedimentary rock involves what processes?

compaction and cementation

At which type of boundary are we likely to find the highest mountain ranges (Ex. the Himalayas)?

continental collision (continental-continental convergent boundary) bc continents don't subduct

At which geologic setting would regional metamorphism be most likely to occur?

convergent boundary

Divergent boundaries typically form by __________ and convergent boundaries typically end by __________.

divergent: continental rifting convergent: continental collision

What statement best describes the distribution of earthquakes in ocean basins?

earthquakes are found in linear belts in multiple locations in the ocean basins

Compared to a mafic rock, a felsic rock has a _______ silica content and melts at a ________ temperature.

felsic rock has a HIGHER silica content and melts at a LOWER temperature

Describes the process by which mafic minerals may freeze and sink to the bottom of a magma chamber if a body of magma drops below a certain temperature.

fractional crystallization

Fractional crystallization typically happens when minerals _________. This results in a magma that is _______ mafic in composition.

freeze and sink; less mafic

Contact metamorphism is the result of increased ___________.

heat DOES NOT NEED PRESSURE

Which of the following statements is consistent with hot spots?

hot spots can be found in the middle of plates and also along the edges of plates they come from rising heat in the mantle and therefore do not require plate boundaries movement to occur

Temperature _____________ and pressure _____________ as you go deeper within the Earth.

increases, increases

Which of the following is NOT a suitable method of managing mass wasting?

increasing the grade of a slope by planting vegetation at the top is NOT good -vegetation increases mass movement

The meanders of a river tend to grow ________ over time since a river's velocity (and thus ability to cause bank erosion) is ________ on the outside of a meander bend compared to the inside of a meander bend.

larger; higher

Gases escape more easily from a _______ viscosity magma; that is why eruptions are more violent from volcanoes that are supplied by _____ viscosity magma. these violent eruptions are typically sourced from _____ magma

low, high, felsic

Describes a scenario in which the composition of a magma may vary owing to its proximity to another body of magma.

magma mixing

creep

movement to the right

Marble, a(n) ___________ metamorphic rock, is formed from the metamorphism of ___________.

non-foliated;limestone

Which statement is the most accurate? -Old oceanic crust is generally located very far from oceanic ridges. -Really young oceanic crust surrounds all of Antarctica. -Young oceanic crust is most commonly found at deep-ocean trenches. -The oceanic crust along the west coast of South America is older than any oceanic crust in the Atlantic Ocean.

old oceanic crust is generally located very far from oceanic ridges

Imagine that you have a continent to your left and an ocean basin to your right. If the ocean basin is subducting beneath the continent (convergent boundary), where are you likely to find volcanoes?

on the edge of the continent

Which of the following Earth layers are wholly or mostly liquid? Select all that apply.

outer core -part of mantle but it is NOT mostly liquid

Describes the process by which a higher temperature is necessary to melt mafic rock as compared to felsic rock.

partial melting

Which of the following is NOT one of the most common elements found on or within planet Earth?

phosphorus is NOT common -silicon, iron, magnesium, aluminum, and sodium ARE common

The lithosphere is distinct from the asthenosphere because _________.

the lithosphere is rigid and the asthenosphere can behave plastically

Initially, why wasn't the idea of continental drift widely accepted?

there was no way to explain how the continents moved

The variation in elevations across Earth's surface is known as ____________.

topography

Which statement best describes the impact that urbanization (i.e., building cities) has on flooding?

urbanization tends to increase flooding because less rainwater can infiltrate into the ground

what statements are true regarding seismic waves? 1. A recording from a single seismogram will tell you the direction the seismic waves came from. 2. P-waves typically have the largest amplitude (height) when viewed on a seismogram. 3. P-waves and S-waves are both travel through the interior of Earth rather than along the surface. 4. P-waves travel fastest and are the first to arrive at a seismometer station. 5. Seismic waves are caused by the vibration of rock.

-P-waves and S-waves are both travel through the interior of Earth rather than along the surface -p waves travel fastest and are the first to arrive at a seismometer station -seismic waves are caused by the vibration of rock

Rock can be melted by...

-DECREASING the pressure -INCREASING the temperature -adding water

Select all the statements below that accurately describe volcanic activity at various plate tectonic settings.

-although both formed by hot spots, Hawaii's volcanic eruptions are much different than yellowstone's -most of the world's sub-aerial volcanoes are found along convergent plate boundaries -continental rifts can lead to both basaltic and rhyolitic eruptions -predicting the timing of future volcanic eruptions is essentially impossible, but the probability of a volcano erupting can be assessed using recurrence intervals based on geologic record

Which of the following changes indicate that a volcanic eruption may soon happen? Select ALL that apply.

-an increase in heat flow/increase in temperature -surface bulging of the volcano/increase in topography -an increase in gas emissions/gas activity -increased seismic activity

Select those statements from the list below that are TRUE. 1. Creep causes vertical structures such as trees and telephone poles to tilt upslope. 2. Avalanches can happen when frozen snow layers are buried by new snow. 3. Submarine mass movements can trigger tsunamis. 4. Creep causes vertical structures such as trees and telephone poles to tilt downslope. 5. The angle of repose is the steepest angle at which unconsolidated sediments can sit without slipping downhill. 6. Solifluction is a faster-than-usual kind of slump in wetlands. 7. Classification of mass movement events is based on the type of material involved (Ex. rock, regolith, ice, etc.), the velocity and character of the movement, and the environment in which the events take place (Ex. on land or under water). 8. Rock layers dipping into a mountain slope create a greater landslide hazard than rock layers dipping parallel to a mountain slope.

-avalanches can happen when frozen snow layers are buried by new snow -submarine mass movements can trigger tsunamis -creep causes vertical structures such as trees and telephone poles to tilt downslope -the angle of repose is the steepest angle at which unconsolidated sediments can sit without slipping downhill -classification of mass movement events is based on the type of material involved (Ex. rock, regolith, ice, etc.), the velocity and character of the movement, and the environment in which the events take place (Ex. on land or under water)

What is TRUE with respect to how the characteristics of a stream change as you move downstream?

-channel size increases -flow velocity increases -discharge increases -sediment load increases -sediment grain size decreases

Which of the following is NOT a typical weak surface that geologists recognize as a potential failure surface? 1. wet clay layers 2. crystalline igneous rock 3. metamorphic foliation planes 4. joints

-crystalline igneous rock is NOT a weak surface weak surfaces include: -joints -bedding -metamorphic foliation planes / foliated surfaces -wet clay layers / saturated

What are the ways in which a mineral can form?

-crystallization from magma -magma cooling -precipitation from solutions, water, or gas -metamorphism (high heat and pressure) -biological activity -solid state diffusion (transportation of pre-existing minerals) can NOT be formed by the dissolution in water

Which is are defining characteristic for all minerals?

-defined chemical composition/ordered internal structure -specific arrangements of atoms -solid -inorganic -naturally occurring do NOT need to contain more than one element - most contain only one

Mass movement ________________.

-depends on the balance between the downslope force and the resistance force -happens when the slope of a hill gets steeper than the angle of repose -can happen under wet or dry conditions

Where do streams get their water?

-from sheetwash -from the ground / groundwater -directly from rain or snow / precipitation -from melting snow and ice -from outlets of ponds and lakes

Which of the following statements are true with respect to earthquakes at various tectonic settings? Select all true statements.

-in general, deep earthquakes (>100km) only occur at convergent boundaries -both normal and strike-slip faults are common along mid-ocean ridges -continental collisions are typically characterized by movement along reverse faults -continental rifts are characterized by normal faults and shallow earthquakes

Identify the conditions that would be likely to promote metamorphism.

-increasing temperature -increasing pressure -tectonic stress -presence of hot fluids/magma

Select all the options that would accurately complete the sentence below. The lithosphere __________.

-is the outer layer of earth's surface -is rigid

examples of biochemical/organic sedimentary rock

-limestone -chalk -coal -chert

What items would help to distinguish a volcano from a non-volcanic mountain?

-nearby pyroclasitc debris -lahar deposits in nearby river valleys -lava tubes present -presence of a crater at the summit (top)

What observations supported the notions of seafloor spreading and moving continents? Select all that apply.

-seafloor bathymetric maps revealing mid-ocean ridges and deep trenches -maps showing distinct belts of oceanic earthquakes rather than a random distribution across the ocean floor -a striped pattern of seafloor magnetic anomalies that are symmetrical to ocean ridges

Which of the following are associated with divergent boundaries?

-seafloor spreading -fracture zones -magma formation -oceanic ridges

examples of clastic sedimentary rocks

-shale -conglomerate -sandstone -breccia

Which of the following serve to drive plate motion? Select all that apply.

-slab pull -ridge push -convection

Clastic sedimentary rocks are classified on the basis of which factors?

-sorting -size -shape -composition

Which of the following are associated with convergent boundaries?

-subduction zones -magma formation -oceanic trenches -large earthquakes -mountain ranges

Which would either lead to a landslide or make a landslide more likely to occur?

-the angle of repose of a slope increases -a slope becomes saturated with water -weak surfaces dip in the direction of the slope -the downslope force increase

What is TRUE statements about rivers and streams?

-the discharge of a river could potentially decrease downstream if a river is located in an arid region -an oxbow lake forms when erosion cuts across a river meander, thus leaving the meander isolated from the main channel -human activity can have significant impact on the discharge of a stream -deltas form because stream velocity abruptly decreases when entering a larger body of water

What statements below are true regarding faults and earthquakes?

-the focus of an earthquake is the point on a fault where slip begins, whereas the epicenter refers to the point on Earth's surface directly above the slip location -a large earthquake is generally characterized by a lot of slip along a large area of a fault -on average, multiple earthquakes occur every day across the globe -the buildup of stress prior to an earthquake causes elastic deformation in rocks

Of the choices listed below, select all those that are true about the Earth's magnetic field.

-the magnetic poles move and can even flip -the magnetic field is generated by swirling liquid iron surrounding earth's inner core -the magnetic field deflects dangerous particles traveling via the solar wind -it is similar to a bar magnet

Select all of the following statements that are true with respect to the crust, lithosphere, and tectonic plates. Recall that crust and lithosphere are not the same thing!

-there are 3 types of tectonic plate boundaries -oceanic crust is more dense than continental crust -oceanic crust covers more of the earth's surface than continental crust

Which of the following statements apply to composite/stratovolanoes volcanoes (rather than shield volcanoes)?

-they are capable of producing extremely violent eruptions -they are typically sources by high-viscosity magma -they form alternating layers of lava and tephra

examples of chemical sedimentary rocks

-travertine -evaporates -rock salt -dolostone

Which of the following hazards are associated with earthquakes?

-tsunami -ground shaking -building collapse -liquefaction -disease -fire -landslides -subsidence -lateral spreading

indicate whether the characteristic applies to volcanic igneous rocks, plutonic igneous rocks, or both: 1. contains minerals 2. form at earth's surface 3. can form from magma from asthenosphere 4. present at earth's surface only after erosion 5. classification is based on both color and texture 6. can have vesicles 7. can form from melted continental crust

1. both 2. volcanic 3. both 4. plutonic 5. both 6. volcanic 7. both

What are the steps in the formation of a clastic sedimentary rock?

1. breakdown / weathering 2. transportation / erosion 3. deposition 4. lithification (compaction and cementation)

Match the statements to the appropriate class or type of sedimentary rock: 1. This rock is formed by the actions of microscopic marine organisms 2. Gypsum is an example of this class of sedimentary rock 3. Weathering is a key process in the formation of this class of sedimentary rocks 4. This rock type could be either formed by chemical or biochemical processes

1. chalk 2. chemical 3. clastic 4. limestone

Indicate whether each process is an example of physical or chemical weathering by writing 'physical' or 'chemical' in the blank following each statement: 1. Slightly acidic rainwater slowly eats away at a limestone outcrop. 2. Water seeps into the cracks of a rock, then freezes and expands, making the crack larger. 3. An igneous rock like granite, which was formed under high temperatures and pressures, splits into onion-like sheets when exposed to the low pressures of Earth's surface. 4. A humid climate with lots of rain causes some of the minerals in a rock to swell and weaken the rock. 5. A layer of rust forms on a rock that is composed partly of iron-rich minerals. 6. Humans dig a quarry to mine mineral resources.

1. chemical 2. physical 3. physical 4. chemical 5. chemical 6. physical

which of these statements are true and which is false? 1. Mud cracks found in sedimentary rocks are strong indicators that the sediment was formed in a marine environment. 2. Changing environmental conditions at a given location can lead to the deposition of a series of distinct sedimentary beds. 3. A sequence of sedimentary rocks made up of layers of fine clay and plankton shells suggests the sediment was deposited in the deep ocean. 4. Ripple marks, dunes, and cross beds are formed when a moving fluid (ex. air, water) creates certain shapes and patterns in the deposition of sediment.

1. is FALSE 2-4 are TRUE

Which of these are prevention and which are adjustments? 1. levees 2. floodplain infrastructure regulation 3. flood control channels 4. increase citizen awareness of flood risk 5. flood proof structures 6. dams 7. management of upstream drainage basin

1. levees - prevention 2. floodplain infrastructure regulation - adjustment 3. flood control channels - prevention 4. increase citizen awareness of flood risk - adjustment 5. flood proof structures - adjustment 6. dams - prevention 7. management of upstream drainage basin - adjustment

Match the listed sediment/rock with its most likely environment of deposition. 1. sandstone 2. fossiliferous limestone 3. coal 4. evaporite 5. shale 6. conglomerate

1. sandstone - beach 2. fossiliferous limestone - shallow ocean 3. coal - swamp 4. evaporite - restricted basin 5. shale - lake bottom 6. conglomerate - mountain stream

During any given year, what is the probability (give your answer in percent!) that a 20-year flood will occur? Your answer should be between 0-100%.

5%

Which of the following statements best describes a scientific hypothesis?

An interpretation made based on collected scientific data and/or observations.

According to the textbook, what are some of the practical benefits of studying geology?

Knowledge of natural resources, including how they are formed and extracted, and how that controls their availability and cost. A general understanding of how science works. An ability to better decipher media regarding natural hazards and/or environmental issues. An understanding of the ways in which various materials and processes interact to change the planet over time.

In your own words and in complete sentences, explain the difference in the formation of magma at subduction zones versus the formation of magma at divergent boundaries.

Melting occurs at divergent boundaries because the asthenosphere rises toward Earth's surface and subsequently melts as a result of decompression. Melting occurs at subduction zones (convergent boundaries) because volatile materials such as water diffuse from the subducting crust into the overlying asthenosphere, causing flux melting (melting that occurs because the addition of water lowers the overall melting temperature of the rock).

Identify the TRUE and FALSE statement about floods. 1. One hazard posed by flooding is the contamination of drinking water supplies. 2. A flood does not necessarily require an intense rainfall event if the ground is already saturated. 3. Flash floods are given this name because they may come without much warning and escape from the floodwaters may not be possible. 4. Artificial levees serve to reduce the risk of flooding by limiting the amount of water that can enter a channel.

TRUE: -one hazard posed by flooding is the contamination of drinking water supplies -a flood does not necessarily require an intense rainfall event if the ground is already saturated -flash floods are given this name because they may come without much warning and escape from the floodwaters may not be possible FALSE: -artificial levees serve to reduce the risk of flooring by limiting the amount of water that can enter a channel

Granite (a plutonic rock) has a silica content most similar to which volcanic rock?

rhyolite

Which is the most accurate statement about viscosity and magma?

rhyolitic (felsic) magmas have relatively high viscosity and lead to explosive eruptions high viscosity = felsic = high silica content = explosive = gas can't escape easily = flows slowly = lower temperature

Which statement best summarizes the ability of scientists to predict earthquakes?

short-term predictions of earthquakes are essentially impossible, but reasonable long-term assessments of earthquake probability can indeed be made

Within the Earth's crust, which is the most common class of minerals?

silicates

Earthquakes result from __________ along a ___________.

slip; fault

Which of the following statements is most accurate with respect to the terms gem and mineral?

some gems are less common varieties of some otherwise fairly common minerals

What was Alfred Wegener's continental drift hypothesis?

the continents were formerly united in a supercontinent known as pangaea

When reading a seismic record from a seismometer, the delay between the arrival of the P-wave and S-wave is a function of what?

the distance between the seismometer and the earthquake -The longer the distance between the seismometer and the earthquake, the greater the gap between P waves and S waves since they travel at different speeds.

If a hillside gets wet, which of the following statements best describes what will happen?

the downslope force increases, making the slope more likely to fall

If it were to rain everywhere in the United States on the same day, into which body of water would most of this water ultimately flow (even if it may spend quite a bit of time underground before getting there)?

the gulf of mexico