Intro to solid earth lecture: final exam

The deepest part of the ocean floor, along the Mariana trench, is due to

a depression due to the down-bending of the plate as it subducts

What is a "laterite" soil?

a soil in which the zone of leaching is enriched in iron and/or aluminum

Hematite is one product of chemical weathering on Earth. Which of the following is another product of chemical weathering?

clay

Why is clay common in soil? Because ...

clay is formed by weathering of feldspar, the most abundant mineral in the crust

'Good soil' for agriculture contains...

clay, sand, and silt

In which soil horizon is bauxite found (the ore of aluminum)?

E - zone of leaching

Very often, the first sign that a volcano might erupt is the occurrence of...

Earthquakes

What is the main reason tectonic plates are moving?

The plates are dense and want to move into the asthenosphere

Which of the following were erupted or produced during the 1980 eruption of Mt. St. Helens?

- Ash fall - Pyroclastic flows - Lahars - Volcanic dome

Evolution through natural selection:

- Has been tested many times. - Is what is taught in science classrooms because it is scientific. - Is the hypothesis (now theory) that Darwin proposed to explain evolution. - Makes many testable predictions.

Which of the following is a fact?

- In the past, as temperature rose, CO2 also rose. - the recent rise in CO2 is man-made. - CO2 is a greenhouse gas. - prior to the recent rise in global temperature, average temperatures were declining.

Which factor triggers landslides?

- heavy rains - earthquakes - over steepened slopes - removal of vegetation

Which of the following factors will make a rock behave more ductile rather than brittle?

- higher temperature - higher confining pressure - lower strain rate - a rock type prone to ductile behavior

Volcanic ash...

- is the result of explosive eruptions - is the smallest type of pyroclastic material - makes up most of a volcanic eruption column - can travel far and blanket the landscape

Which of the following is a factor in soil formation?

- parent material - time - climate - topography

what are some facts about the atmosphere's

- the average temperature of Earth's atmosphere has been increasing since the Industrial Revolution - Prior to the Industrial revolution, the temperature of the atmosphere was decreasing - Atmospheric temperatures have been fluctuating over the past 400,000 years due to variations in the Earth's orbital parameters - the increase in atmospheric CO2 since the Industrial Revolution is largely man-made

Climate (average global temperature) has fluctuated a lot in the past. Why are scientists concerned then about the current burning of fossil fuels?

- we are adding CO2 at an extremely rapid rate - we are adding more CO2 than the atmosphere has had in the past 400,000 years - ecosystems may not have time to adjust to climate change - human populations may not have time to adjust to climate change

If the water table at point A is at an elevation (above sea level) of 200 m and the water table at point B is at 100 m, and locations A and B are 1,000 m apart, the hydraulic gradient is

0.01

A common way to describe a portion of the electromagnetic spectrum is Hertz. What is hertz?

A measure of the frequency (in per second)

Approximately how many tectonic plates are involved in the Pacific Ring of Fire?

10

Typically, in the Earth's crust, how many O ions surround the central Si ion and what shape is made?

4, making a tetrahedron

If you had a volume of 10 liters of good loam soil and you squeezed out all the air and water, approximately how much volume would the sample of soil now occupy?

5 liters

Which of the following comes closest to the percentage of the US land area covered by the Mississippi River drainage basin?

50%

The figure below has both the P and S wave travel time curves. An earthquake occurs. If the P-wave arrived at station "A" at 9:32 AM and the S-wave arrives 9:40 AM, approximately how far away was the epicenter? (Note the time scale on the y-axis is in 2 minute intervals!)

6,000 km

The largest mass extinction on Earth is thought to have been caused by

A flood basalt eruption

Assuming iridium falls to earth at a constant rate from cosmic dust, which of the following is a correct statement?

A high sedimentation rate of limestone would result in low iridium concentrations in the limestone.

What is the key difference between an earthquake prediction and an earthquake early warning system?

A prediction refers to earthquakes that have not yet happened, an early warning refers to earthquakes that have already started.

Which of the following is a set of ideas that explains several observations and involves ideas that have been (positively) tested?

A theory

Based on the figure, which electron jump/drop would absorb/emit red?

A-B

Why do large explosive volcanic eruptions cause cooling of the near-surface environment of the Earth in the few years after a large eruption?

Aerosols and fine ash block the sunlight

Which of the following elements was not on our list of those that commonly cause color in minerals?

Al (aluminum)

The following choices give the drop in elevation of a stream over a certain distance. Other things being equal, which stream would have the fastest velocity?

All should have equal velocities

Why do some horizons in soils contain a lot of aluminum?

Aluminum is enriched in the soil as other elements are leached/removed

David Johnston, the volcanologist who perished at Mt. St. Helens did not expect the volcano to erupt when it did. Why is that?

An unexpected earthquake triggered a landslide that "uncorked" the volcano

The Pacific Plate is one of the fastest-moving plates. Which of the following plates is not moving much at all?

Antarctic Plate

Evolution, the idea that life--as preserved in fossils--has changed over time is considered a fact:

Because anyone can go see for themselves (make the observation) that fossils have changed over time.

Why is there an upper limit to the size of an earthquake?

Because rocks/faults have an upper limit to their strength or frictional resistance.

All of the following volcanic products/effects cause cooling of the atmosphere except:

CO2 gas

Why are the world's oceans getting more acidic?

CO2 is rising in the atmosphere

The Himalayas are at which type of plate boundary?

Continent-continent convergent

Mount St. Helens, part of the Cascadia volcanic belt, is at what type of plate boundary?

Convergent

Very explosive volcanoes are associated with which type of plate boundary?

Convergent

Based on their original assumptions, the iridium that the Alvarezes measured in the K-T boundary clay layer was thought to have come primarily from?

Cosmic dust

What is one major factor why the Mississippi delta is getting eroded away by the ocean? Because...

Dams along the river prevent new sediment from reaching the delta

The area of the Red Sea is an example of which of the following?

Divergent boundary

One morning, you find that your lamp won't turn on. You ask yourself why the lamp won't work. You hypothesize that your lamp bulb is broken. Which of the following is a proper prediction from your hypothesis?

If I replace the bulb with a new one, then the lamp will turn on.

Which of the following is the correct order of some steps in the scientific method?

Initial observation, question, hypothesis, prediction, test the prediction

Which of the following is a measure of the amount of damage that occurs at a particular place due to an earthquake?

Intensity

The core of the Earth is made up mostly of

Iron

Why is there volcanism in Hawaii?

It is above a rising mantle plume

In the same figure below, which fault would you expect to find in a region that also has a lot of folding?

Just strike slip faults

The "plates" in plate tectonics are made up of:

Lithosphere

Which of the following is the key step in the scientific method that best separates it from non-scientific methodologies?

Making a testable prediction

The monstrous flood basalt eruptions are thought to be caused by:

Mantle plumes & Pulling apart of lithospheric plates

Mount Rainier, Mount Hood, Mount Adams, Mount Shasta, and Mt. St. Helens are all volcanoes of the Cascade Range in the Pacific northwest. Which volcano is the most active?

Mt St. Helens

The series of figures below shows a map view of a fault (black line) with six markers that were placed in the year 2001 (leftmost figure). The next three figures show the points as they were surveyed the following three years. This fault has not produced an earthquake in a long time. Should the people living near this fault be concerned? Why?

No, because the fault appears to be just creeping.

In the figure below, which fault would result from extension--- i.e., pulling the crust apart?

Normal

If the hanging wall of a fault moves down relative to the footwall, what type of fault is it?

Normal fault

What are the two most abundant elements in the Earth's crust?

O and Si

How many North magnetic poles does the Earth have?

One

In the figure below why does there appear to be a decline in volcanic eruptions during World War I and World War II?

People were busy fighting the war(s) and therefore did not report volcanic eruptions

A fault is discovered to be running through a neighborhood. They learn that you've taken an earth science class and ask you if the fault is dangerous in terms of earthquakes. What's the best answer?

Possibly dangerous

What is a key factor that can help someone who is using the scientific method help her come up with good hypotheses, good predictions, and effective ways to test the predictions? Lack of this factor might prevent a Nobel Prize-winning physicist from being a great geologist, say.

Previous knowledge

Which of the following describes the relationship between wavelength and energy of the electromagnetic wave?

Shorter wavelength corresponds to higher energy

Below is a list of solids with their corresponding melting points. Which substance is held together by the weakest bonds?

Solid Argon = - 189 C

On the radio the other day, I heard someone say "subduction is caused by continental drift." This is incorrect. Which of the following statements best describes the relationship between continental drift and subduction?

Subduction causes plates to move, which carry the continents along (continental drift)

There is an outer strong layer (the plates) and an inner weaker zone in Earth because of differences in which factor:

Temperature

One prediction that the Alvarezes had and which they tested and published in their original 1980 paper was:

The K-T boundary clay should have a different composition than clay found in the limestone above and below the clay layer.

Which of the following was a dramatic global effect of the 1815 eruption of Tambora in Indonesia?

The following year had unusually cool/cold global temperatures

Although the magnetic poles wander about over time, over thousands of years, the average positions of the magnetic poles coincide with:

The geographic poles

The "Pacific Ring of Fire" is

The zone of explosive volcanoes around the pacific

Although continental drift was proposed in 1912 and even earlier, it was not accepted by most geophysicists until the late 1960s. Why?

There was no viable mechanism for continental drift

All of the following are characteristics of "P-waves" except:

They travel only through solids.

How many K-T boundary clay sites did the Alverezes study in their original 1980 paper?

Three in Italy, Denmark, and New Zealand.

The Arabian plate is moving roughly northward. On its west side, where the Dead Sea is, what type of plate boundary would you expect?

Transform

Earthquakes are associated with which type of boundary?

Transform, Divergent, and Covergent

Which of the following bonds allows electrically neutral molecules to bond and eventually solidify?

Van der Waals bond

"Vesicles," which are holes in a volcanic rock are due to which component in a magma?

Volatiles

The components of a magma that prefer to be in the gaseous state near the Earth's surface are called

Volatiles

The rock described in no. 1 above is said to have a

Volcanic texture

Prior to modern plate tectonics, there was a theory that the Earth was/is shrinking thereby causing wrinkling of the Earth's outer crust as the "skin" was compressed that produced mountains much like the wrinkling of a dried out apple's or grape's skin. If this were true, which of the following would you expect then:

We should only have mostly fold and thrust mountains in the crust

When CO2 is dissolved in water, it makes:

carbonic acid

The table below gives the distances to the epicenter of an earthquake determined from three different seismic stations: W, Y, and Z. The figure below is a map with a scale and showing the locations of the three stations (black squares). Which cross "+" indicates the approximate location of the epicenter of the earthquake?

a

Which of the following is an atom that has lost one or more electrons?

cation

Shield volcanoes are characterized by all of the following except:

about half pyroclastic material

Of all the near-surface liquid freshwater, approximately what percent is groundwater?

almost all of it (~99%)

Which of the following important metal is mined from a type of soil?

aluminum

Prior to the recent rise in average global temperatures, what was the main cause of large variations in earth's average surface (atmospheric) temperature over the past ~400,000 years?

amount of solar radiation received by the Earth's surface.

Impermeable rock formations that impede/prevent groundwater flow are called:

aquitards

Electrons are transferred or are shared between some atoms because:

atoms want to have complete outer shells

In the figure below, a see-through block of the Earth's crust is shown with a fault cutting through the block that has generated an earthquake at point "c". Which point is the epicenter? (a and b are on the upper surface; c and d are on the fault.)

b

The figures below show cross sections of a stream channel. The upper figure shows the stream during normal flow. The lower figure shows the stream during flooding. Which of the labeled locations would have the highest velocity?

b

If there is a really prolonged drought, what effect will that have on the water table? The water table ...

becomes flatter and lower

What is the type of load shown in the figure below?

bed load

Which of the following climate conditions would favor the least amount of weathering?

below freezing and dry all year round

Which of the following colors has the highest energy?

blue

In the cross section figure below, a well at "X" is pumping out a heck of a lot of water from groundwater. Which of the five other wells is likely to go dry first as a result of the excessive pumping at X?

c

In the map figure below, the level of the water table above sea level is given for 5 points (circles/dots). Which direction will groundwater likely flow (from the point where all the arrows meet)?

c

Imperceptibly slow mass wasting is called:

creep

The figure below shows the same situation as above with the well at x pumping a lot of water. A toilet has been placed as shown with a septic tank below. Which is the worst location to sink a drinking well due to possible contamination from the septic tank?

d

A lahar is an example of a

debris flow

The volume of water passing a certain point of the stream per unit time is called:

discharge

The type of deformation wherein a rock does not return to its original shape and the rock does not fracture.

ductile deformation

Still referring to the last figure, which location has the lowest velocity?

e

The figure shows the same water table as above. If a septic tank (where sewage is dumped) is placed at X, where is the safest place to sink a drinking well?

e

The particle that carries the negative charge in an atom is the:

electron

The largest volcanic eruptions to ever happen on Earth are called:

flood basalt eruptions

The hydrothermal phenomenon wherein mostly steam comes out of the ground is called a:

fumarole

Tropical climate is necessary to produce thick laterite soil but is insufficient. What else is necessary?

gently rolling topography

Which of the following metamorphic rocks forms at a higher temperature than schist?

gneiss

The combination of viscosity ("stickiness") and volatile (gas) content of magma that leads to explosive eruptions is

high viscosity, high gas content

What is the role of confining pressure or depth in the earth on the style of deformation of rock?

higher confining pressure promotes ductile behavior

What is the effect of temperature on the style of deformation of rock?

higher temperatures promote ductile behavior

Why does the silica tetrahedron bond with other ions? Because ...

it has an overall negative charge and can therefore bond to cations

All of the following are false about Yellowstone, except

it is an area of high heat flow

The volcanic phenomenon that has done the most damage and caused the most deaths throughout history are

lahars

Which of the following is the best soil for agriculture?

loam

Downslope movement of regolith driven by gravity wherein the material is not carried in some moving medium like air, water, or ice, is called:

mass wasting

The process that creates V-shaped valleys is

mass wasting

Which of the following is not a factor that goes into calculating the Moment Magnitude of an earthquake?

maximum acceleration at the epicenter

Carbon dioxide is a greenhouse gas. What is another greenhouse gas?

methane

Large amounts of coal deposits suggest that that area of a continent formed:

near the equator

If an area of a continent contains a lot of limestone, what would you expect the magnetic inclination of those limestones to be?

nearly horizontal

The Basin and Range province in North America is a place where the crust is being pulled apart. What types of structure would you expect to be forming in this area?

normal faults

Arrange the following types of lava in order of increasing viscosity (resistance to flow):

pahoehoe, aa, block lava, volcanic dome, volcanic spine

In the last two questions, what is the factor causing the difference in velocities?

proximity to the ground/bottom of the water where drag is happening

Most groundwater comes from and is resupplied by:

rain and snow

The loose, weathered, and partially weathered material near the Earth/s surface is called:

regolith

If you find a very widely scattered layer composed of a jumble of rocks without any muddy material in-between the rocks, the deposit was likely produced by a:

rock avalanche

A type of downslope movement that occurs rapidly and with no, or very little, water:

rock slide

A depression on the Earth's surface due to sinking or collapse of the superficial material into a cavity below produced by dissolution of rock like limestone is called:

sinkhole

Streams tend to do more erosion in the mountains, whereas they tend to deposit more sediment in the lowlands. Why is this so?

slopes/gradients are steeper in the mountains

The weird shapes of rocks in Elephant Rocks State Park in Missouri is due to

spheroidal weathering

The explosive volcanoes of the Pacific Ring of Fire are

stratovolcanoes

An igneous rock is composed entirely of fairly large crystals that are clearly visible. This implies that:

the magma cooled slowly

The term "supervolcano" is now a formal scientific term describing some types of eruptions. Which of the following is true?

the term was first used by the British Broadcasting Corporation in a documentary

If an area of a continent contains a lot of volcanic rock, what would you expect the magnetic inclination to be?

there is no expected relationship between abundant volcanic rocks and the magnetic inclination

Why are magmas that are high in silica (SiO2) also high in viscosity? Because...

they are more polymerized

If streams were the only agents of erosion, what would be the shapes of valleys?

they would be steep-sided slot canyons

In a good loam soil, the role of sand and silt is to allow excess water to drain away. What is the role of the clay?

to retain some water in the soil

According to news reports, the areas that have experienced recent forest fires in California are now susceptible to "mudslides" (muddy debris flows). Why do you think this is so?

vegetation has been removed by the fires

The main factor that determines how erosive or how large a particle a stream can move is the stream's :

velocity

Which of the following is the soil horizon right below the zone of leaching?

zone of accumulation