Geology 120 Exam 2

Which of the following are advantages of using natural gas to generate electricity? (choose all that apply)

-- It is plentiful right now. -- It is an on-demand energy source. -- It has less emissions than coal -- It is inexpensive right now.

Which of the following are advantages of using nuclear energy to generate electricity? (choose all that apply)

-- It is relatively safe -- On-demand energy source -- Very low emissions of carbon dioxide and air pollutants -- Has a high energy output

If the price of a mineral resource increases, which of these may occur? (choose all that apply)

-- Mining may increase to increase the mineral supply -- Consumers or product makers may seek a substitute mineral or product -- Consumer demand for the mineral resource may decrease

Which of the following factors would cause the cut-off grade of a mineral resource to rise? (Choose all that apply.)

-- More stringent environmental regulations -- Rising energy costs -- Better (more equitable) labor agreements

Which of these are true statements about rare earth elements (REE)? (select all that apply)

-- REEs have partially filled f electron orbitals -- REEs are elements include the Lanthanide group and Yttrium

Which of these are advantages to using solar energy to generate electricity? (choose all that apply)

-- Renewable energy source -- It has very low emissions of carbon dioxide and air pollutant -- Fuel source is free

Which of the following changes to the crust would act to increase regional elevations? (Choose all that apply.)

-- decrease the density of the crust -- heat the crust -- thicken the crust

Hydraulic fracturing ______________ (select all that apply).

-- is primarily used to extract oil or gas from shale -- increase the permeability of the rock -- allows oil and gas to be extracted from source rocks -- is a process in which fluid and sand is pumped at high pressure into a rock to fracture it

For oil to be produced, the following events must occur: (choose all that apply)

-- microorganisms settle to the bottom of an ocean or lake after they die -- organic molecules are preserved under low oxygen conditions -- microorganisms produce organic molecules through photosynthesis -- organic molecules are buried to greater depth by the accumulation of sediment

Which of these energy sources can generally produce electricity "on-demand"? (select all that apply)

-- nuclear -- natural gas -- coal -- hydroelectric

Which of the following are ways of correlating rocks? (Select three that apply)

-- rock type -- time (age) -- fossils

Which of the following are possible impacts of over-pumping groundwater? (select all that apply)

--ground subsidence -- shallow wells become dry -- declining water table

Groundwater flow will be faster if _______________. (select all that apply)

--the hydraulic gradient is higher -- the permeability is higher

Potassium-40 is radioactive and decays into Argon-40. The half-life of Potassium-40 is 1.3 billion years. You measure the # of atoms of each isotope in a rock and find 750 atoms of Potassium-40 and 250 atoms of Argon-40. Approximately, how old is this rock?

0.65 billion years old

Approximately what percentage of the water on Earth is liquid, fresh water?

1%

C-14 (Radiocarbon) is radioactive and decays into N-14 with a half-life of 5730 years. Assume a rock starts with 20,000 atoms of C-14. if the rock is 22,920 years old, how many C-14 atoms should be left?

1,250

If a metal ore has an average ore grade of 4%, how many pounds of ore must be mined in order to obtain 50 pounds of that metal?

1,250

Put the events listed below in the order they must have occurred to explain the features that we see at Siccar Point from first (1) to last (5)

1- Deposition of the muddy gray sandstone 2- Folding and uplift of muddy gray sandstone 3- Erosion down into muddy gray sandstone 4- Deposition of the reddish sandstone 5- Tilting and uplift of both the muddy gray sandstone and the reddish sandstone

The block diagram above shows the various rock units that can be found in the Grand Canyon. Using the Principles of Relative Dating, put the rock units in order from oldest (1) to youngest (19). (Heck this question)

1- Vishnu 2- Zoroaster 3- Bass 4- Hakatai 5- Shinmo 6- Dox 7- F the lil crack in the rock 8- Cardenas 9- Tapeats 10- Bright Angel 11-Mauv 12- Temple Butte 13- Redwall 14-Supai 15- Hermit 16- Coconino 17- Toroweap 18- Kaibab 19- top layer w volcanoes or something

Rank these fossil fuels by the amount of carbon dioxide emissions produced for a given amount of energy produced from 1 (most CO2) to 3 (least CO2).

1- coal 2- oil 3- natural gas

Using the image shown below and your relative dating principles, put the rocks in the order that they formed from oldest (first - 1) to youngest (last - 8).

1-C 2- H 3- E 4- G 5- A 6- F 7- D 8- B

If a metal ore has an average ore grade of 25 ppm, how many metric tons of ore must be mined in order to obtain 30 grams of that metal? (remember there are 1,000,000 grams in 1 metric ton)

1.2

Potassium-40 is radioactive and decays into Argon-40. The half-life of Potassium-40 is 1.3 billion years. You measure the # of atoms of each isotope in a rock and find 250 atoms of Potassium-40 and 250 atoms of Argon-40. How old is this rock? Give your answer in billions of years.

1.3

After 3 half-lives, what percentage of the original parent isotopes would still be present?

12.5%

If a metal ore has an average ore grade of 50 ppm, how many grams of ore must be mined in order to obtain 10 grams of that metal?

200,000

After 2 half-lives, what percentage of the original parent isotopes would still be present?

25%

Approximately, what percentage of Colorado's electricity is currently generated from renewable energy sources?

25%

C-14 (Radiocarbon) is radioactive and decays into N-14 with a half-life of 5730 years. Assume a rock starts with 1000 atoms of C-14. if the rock is 11,460 years old, how many C-14 atoms should be left?

250 (with margin:0)

If a metal ore has an average ore grade of 15 ppm, how many metric tons of ore must be mined in order to obtain 45 grams of that metal? (remember there are 1,000,000 grams in 1 metric ton)

3

If there are 125 atoms of the parent isotope remaining and 875 atoms of the daughter isotope in a rock, how many half-lives have passed since the rock formed?

3

Approximately what percentage of the water on Earth is fresh water?

3.5%

What percentage of freshwater is groundwater?

30.1%

Potassium-40 is radioactive and decays into Argon-40. The half-life of Potassium-40 is 1.3 billion years. You measure the # of atom of each isotope and find 50 atoms of Potassium-40 and 750 atoms of Argon-40. How many half-lives have passed since the rock formed?

4

What is the currently scientifically accepted age of the Earth?

4.54 billion years old

If a metal ore has an average ore grade of 2%, how many pounds of ore must be mined in order to obtain 100 pounds of that metal?

5,000

C-14 (Radiocarbon) is radioactive and decays into N-14 with a half-life of 5730 years. You have measured the number of atoms of C-14 in a piece of charcoal from an archeological site and find 500 atoms. Assuming the charcoal started with 1000 atoms of C-14, how old is the charcoal? Give your answer in years.

5,730

If a metal ore has an average ore grade of 10 ppm, how many grams of ore must be mined in order to obtain 20 grams of that metal?

500,000

The diagram below shows the when different clams of the genus Mytiloides lived. If you find fossils of M. hattiru, M. kossmati, M. columbiarus, and M. lobiatus in the rock, but do not find M. subhercynius, which of these is the most likely age of the rock?

92.8Ma

beta decay

A neutron in its nucleus splits into an electron and a proton

electron capture

A proton in the nucleus captures an electron from one of the electron shells and becomes a neutron

normal fault

A type of fault where the hanging wall slides downward; caused by tension in the crust

nonconformity

An unconformity in which older metamorphic or intrusive igneous rocks are overlain by younger sedimentary strata.

Which type of coal has the highest carbon content?

Anthracite

Which list contains the names of the three eons in order from oldest to youngest?

Archean, Proterozoic, Phanerozoic

In which of these Geologic time intervals did humans first appear?

Cenozoic

Which of these countries produces most of the world's supply of rare earth elements?

China

The map below shows the annual water balance for different parts of Colorado. Which area would you predict is more heavily dependent on groundwater? (couldn't see the pic)

D

The stratigraphic column below shows descriptions of the rock layers below Fort Collins. Which of the following would be the best choice for a source of groundwater?

Dakota Sandstone

Match the plate boundary type below with the correct type of stress. Divergent Convergent Transform

Divergent = tension Convergent= compression Transform= shear

Which statement best describes the current state of US energy production and/or consumption?

Fossil fuels represent more than 80% of US energy consumption and the US is the world's largest oil producer.

The map below shows elevation of the water table in Long Island, NY. Which of these best describes the direction of groundwater flow?

Groundwater flows from the interior of the island towards the coast line.

What are the two primary sources of water for the City of Fort Collins?

Horsetooth Reservoir, Cache la Poudre River

Organisms that lived for relatively short time periods are particularly useful for dating rocks, especially if they were distributed over a wide geographic area and so can be used to compare rocks from different regions. These organisms are known as ____________.

Index fossils

What are the two largest uses of water in the United States?

Irrigation, Thermoelectric power

On the map below the brown lines indicate surface elevations and the blue lines show the elevations of the water table. What best explains the location of lakes in this region?

Lakes occur where the water table intersects the land surface

In which of these Geologic time intervals did the dinosaurs live?

Mesozoic

If the cost of mining and processing a mineral resource is higher than the value of the mineral resource, which of these will likely occur?

Mining will decrease

Which of these Northeastern Colorado formations has most of the oil and natural gas being extracted from during the oil and gas boom of the past decade?

Niobrara Formation

The stratigraphic column below shows descriptions of the rock layers below Fort Collins. Which of the following would likely make the best aquifer?

Niobrara Group

Rank these reservoirs of water according to their volume. (1 = greatest volume; 4 = least volume)

Oceans, Glaciers and Ice Sheets, Groundwater, Rivers and Lakes

In which of these Geologic time intervals did the first animals with shells appear?

Paleozoic

Which of these Geologic time intervals was the longest and constituted almost 90% of Earth's History?

Precambrian

Using the image shown below, how would you know which rock is older H or C? i.e. which of these relative dating principles would be most useful?

Principle of superposition

Which of these is considered the biggest hurdle in the path of REE production?

Processing REE ore

Which type of fault is best matched with the appropriate plate boundary?

Right-lateral strike-slip fault and transform boundary

Which is the best description of an aquifer?

Rock or sediment below ground that accommodates the flow and storage of groundwater.

In the figure below, which of the following shows an angular unconformity?

Surface B

What determines the ore grade of a mineral resource?

The concentration of the mineral resource in the rock

What is the cut-off grade of an ore?

The lowest grade of an ore that is profitable to mine

How does the price of a mineral resource usually respond when consumer demand for that mineral increases?

The price increases

How does the price of a mineral resource usually respond when the supply of the mineral resource is reduced?

The price increases

Which of the following statements about the half-life of a radioactive isotope is true?

The term half-life refers to the time it takes for half of the radioactive parent atoms to decay into daughter atoms

Which of these most accurately describes the relationship between China's export quota of REE and REE Price?

The two are inversely related; when the export quota is increased, the price decreases, and vice versa.

alpha decay

Two protons and two neutrons are emitted from the nucleus of an atom

inclusions

When one rock formation contains pieces or inclusions of another rock, the inclusion is older than the host rock

Which of these fuel sources are currently the least expensive to build and operate in Larimer County, according to the "levelized cost of energy (LCOE)"?

Wind

Are rare earth elements currently being mined in the United States?

Yes, there is one operational mine in California.

disconformity

a break in a sedimentary sequence that does not involve a difference of inclination between the strata on each side of the break.

Monocline

a fold in rock layers in which both limbs remain horizontal

Syncline

a trough or fold of stratified rock in which the strata slope upward from the axis.

strike-slip fault

a type of fault where rocks on either side move past each other sideways with little up or down motion

reverse fault

a type of fault where the hanging wall slides upward; caused by compression in the crust

angular unconformity

an unconformity in which younger sediment or sedimentary rocks rest on the eroded surface of tilted or folded older rocks

What type of structure is the man standing in front of in this image?

anticline

What is the Principle of Cross-cutting Relationships?

any geological feature that cuts across, or disrupts another feature must be younger than the feature that is disrupted

What is the Principle of Inclusion?

any rock fragments that are included in rock must be older than the rock in which they are included

faunal succession

assemblages of fossils contained in strata unique to the time they lived in and can be used to correlate..

______________ the water table, all of the pore spaces are saturated with water.

below

If a region has extensive reverse faulting and folding, would you expect that region to have high regional elevation, high relief, or both?

both high elevation and high relief

Which type of deformation occurs at shallow depths within the crust?

brittle

Which of the following would likely have the lowest permeability?

clay

Which energy source currently produces the most electricity in Colorado?

coal

Since the early 1980's, water use in the United States has _____________.

decreased

The image below shows an unconformity between limestone on the bottom and sandstone on the top. What type of unconformity is this?

disconformity

Folds are an example of___________deformation that occur at_________ depths in the crust.

ductile, deep

cross-cutting relationships

faults and igneous intrusions that cut across rocks are younger than the rocks they cut across

The foot wall is on the __________ side of this fault. left or right The hanging wall is on the _________ side of this fault left or right

foot:left hanging: right

The map below show contours of the elevation of the water table in the Merced Groundwater Basin in California. What general direction would you expect the groundwater to flow under Merced, CA?

from east to west

Which material would consistently make the best aquifer?

gravel

In the image below there are pieces of a dark metamorphic rock included in a gray granite. Which rock is younger?

gray granite is younger

The concentration of a mineral resource in an ore deposit is generally ____________ than the average concentration in Earth's continental crust.

higher

Whether oil or natural gas is produced in a source rock depends on _________________.

how deep the rock is buried

The rate of groundwater flow is determined by the ______________ and _____________.

hydraulic gradient, hydraulic conductivity

Which of these energy sources would be considered renewable? (select all that apply)

hydroelectric, wind, solar

seal

impermeable rock that prevents migration of oil or gas

Which of these sectors uses the most water in Colorado?

irrigation

original horizontality

layers of rocks deposited from above, such as sediments and lava flows, originally were laid down horizontally

Which site on the cross section below is the most likely setting for an oil field (large accumulation of oil)? (i couldn't find the pic alright)

limestone at D (third layer down on the lumpy)

Which of these is the comparison and correlation of strata within a region by examining the physical properties of the rock and its sequence with other strata.

lithostratographic correlation

___________is the starting material for oil and natural gas, while __________ is the starting material for coal.

marine plankton, swamp plants

What materials were used to determine the age of the Earth?

meteorites

Which of these fossil fuels produces the least amount of carbon dioxide emissions and other air pollutants for a given amount of energy produced?

natural gas

Over the past decade, use of __________ to generate electricity has been increasing in Colorado, and use of __________ has been decreasing.

natural gas, coal

Which of these energy sources produce carbon dioxide as a waste during electricity production (excluding emissions resulting from manufacturing of equipment)? (select all that apply)

natural gas, coal

Isotopes are atoms of the same element but have different numbers of __________.

neutrons

The image below shows an unconformity between granite on the bottom and sandstone on the top. What type of unconformity is this? (I couldn't see the pic so I guessed lmao - def look into types of uniformities) a) non conformity b) angular conformity c) dis conformity

nonconformity

Death Valley is a region that has very low elevation but has mountains with high relief. What type of faults would you predict created the relief in Death Valley?

normal faults

source rock

organic matter-bearing rock within which the formation of gas and oil takes place

Hydraulic fracturing is used to increase the ________________ of an oil or gas-bearing rock.

permeability

______________ describes how well connected the pore spaces in a rock or sediment are.

permeability

Coal was formed through the burial and heating of ____________.

plants

Using the image shown below, how would you know which rock is older H or C? i.e. which of these relative dating principles would be most useful?

principle of cross-cutting relationships

reservoir

relatively permeable rocks that allow migration and accumulation of oil and natural gas

What is the process of fixing, removing, or counteracting environmental problems associated with mining called?

remediation

Which site on the cross section below is the most likely setting for an oil field (large accumulation of oil)? (the pic w like the weird layers but w the granite fault too)

sandstone at D

Which of the following settings would be most favorable for fossil fuels?

sedimentary rocks that contain folds and faults

Porosity generally increases as ________________. (select all that apply)

sorting improves, cementation decreases

trap

structure or arrangement of rocks that leads to the accumulation of oil or gas

The largest mines, producing the most ore, are generally _________________.

surface mines

Which of these types of mining typically produces a greater disturbance of the land and a larger amount of waste rock?

surface mining

superposition

the layers on the bottom are the oldest and the layers above are younger

The contour lines on the map below show the elevations of the water table for a section of the High Plains Aquifer. In what section of the map is the water table highest?

the northwest corner

In the eastern United States, ____________ is the largest use of water.

thermoelectric power

The crust under the Rocky Mountains of Colorado and Wyoming is _____________ the crust under the regions to the east and west of the Rocky Mountains.

thicker than

On the map below the brown lines indicate surface elevations and the blue lines show the elevations of the water table. In what general direction would you expect the groundwater to flow?

toward the bottom right of the map

The map below shows elevation of the water table within the Dakota Aquifer in western Kansas. What is the general direction of groundwater flow?

towards the east

Concentrated deposits of Uranium ore are created by _______________.

transport and precipitation of uranium by groundwater

In a reverse fault, the hanging wall moves ______________ relative to the footwall.

up

Which of the following is NOT a necessary step in the formation of oil and natural gas?

uplift and erosion of organic rich rocks

How is nuclear energy produced to generate electricity?

uranium is split into two smaller particles, releasing heat in the process

Which of the following would likely have the highest porosity?

well-sorted sand

lateral continuity

within the depositional basin in which they form, strata are continuous in all directions until they thin out at the edge of that basin