Geol 100

Place the events in the order they occur between the mid-ocean ridge and deep-ocean trench.

1. Oceanic crust created 2. sediment accumulates on oceanic crust 3. oceanic crust scraped off plate to form accretionary wedge 4. oceanic crust recycled into mantle

Order the steps that lead to seafloor spreading.

1. The asthenosphere beneath diverging plates rises and melts 2. A magma chamber forms beneath the ridge axis 3. Magma rises to the surface and erupts via submarine volcanoes 4. Newly formed crust is moved laterally away from the ridge

Order the events chronologically that occurred in the formation of our Solar System.

1. an accretionary disk formed 2. a protosun formed 3. rings formed in the protoplanetary disk 4. planetesimals collected to form protoplanets

Order the steps in supercontinent formation and breakup.

1. subduction consumes an ocean basin 2. continents collide and form a supercontinent 3. rifting takes place 4. seafloor spreading produces new lithosphere and continents move apart

Place in chronological order the events that led to the formation of the Earth.

1. the earth cleared its orbit of all other matter, making it a true planet 2. the moon formed 3. volcanic activity occurred, releasing gases 4. an atmosphere formed

Place in chronological order the events that led to life as we know it on Earth.

1. the oceans formed 2. photosynthetic organisms appeared on earth 3. oxygen (o2) accumulated in the atmosphere 4. multicellular life developed rapidly on earth

Select statements true of fracture zones.

A.Fracture zones can act as transform boundaries between two actively spreading ridge segments. B.Earthquakes can occur along fracture zones.

Which of the following statements about differentiation are true?Choose one or more: A.The core formed as a result of differentiation. B.The Moon formed as a result of differentiation. C.The Earth is round because of differentiation. D.The mantle formed as a result of differentiation.

A.The core formed as a result of differentiation. D.The mantle formed as a result of differentiation.

Which of the following statements regarding the Big Bang theory are true?Choose one or more: A.All matter in the Universe was once confined to a single point. B.There is no way of knowing how old the Universe might be. C.Earth formed through a series of violent collisions. D.Meteors were responsible for the extinction of the dinosaurs. E.Earth is much older than the rest of the Universe. F.Earth and the Universe formed at about the same time. G.The Universe is considerably older than Earth. H.All stars will end their lives explosively as supernovae.

A: All matter in the Universe was once confined to a single point. G.The Universe is considerably older than Earth.

Which statement(s) is true about igneous rocks? A: All of the possible answers are correct.B. They may form from lava.C. They may form around volcanoes.D. They were molten and have frozen into a solid form.

A: All of the possible answers are correct.

Name the person who proposed the hypothesis of continental drift.

Alfred Wegner

.Order the steps of volcanic island arc formation.

Convergence begins 1) A subduction trench forms where the subducting plate bends downward into the mantle. 2) An accretionary prism begins to form. 3) Magma, created by flux melting of the mantle, rises through the overriding plate. 4) Lava erupts onto the surface, forming volcanoes.

What physical characteristics can be used to distinguish individual rock types? A. compositionB. the size and shape of grains that compose the rockC. textureD. All of the possible answers are correct.

D. All of the possible answers are correct.

This diagram shows a seismic wave passing through the boundary between two rock layers, A and B. Identify the true statement. A. The velocity of the seismic wave is the same through Units A and B. B. Rock Unit A is likely less dense than rock Unit B. C. The ray in this diagram shows wave reflection. D. The ray slows down when it enters rock Unit B.

D. The ray slows down when it enters rock Unit B.

Identify the statement that is true about the Big Bang

It began with all matter and energy concentrated in an infinitesimally small point.

An iceberg will sink into the sea until it displaces its own weight in water, leaving only the "tip of the iceberg" exposed when it floats. Which of the following describes a floating iceberg?

It is in isostatic equilibrium.

What is true of the P-wave shadow zone, shown here?

It results from the lower velocity of P-waves in the outer core.

Which of the following statements about lithosphere and asthenosphere is true?

Lithosphere consists of the crust and the upper mantle and behaves like a rigid layer that breaks or bends rather than flowing like the asthenosphere.

Which of the following statements is true?Choose one: A. Seismic waves travel faster through liquids than through solids. B. P-waves in a porous sandstone will move more slowly than P-waves traveling through a crystalline rock like peridotite. C. Seismic-wave velocity cannot change (increase or decrease) as the waves pass through different rock types. D. S-waves can travel through liquids.

P-waves in a porous sandstone will move more slowly than P-waves traveling through a crystalline rock like peridotite.

Use the graph of P- and S-waves' velocities traveling through the Earth to answer the following question. Why does the line for S-wave velocity disappear in the outer core?

S-waves do not travel through liquids, and the outer core is liquid.

Identify the true statement. Choose one: A. The oldest seafloor can be found along a mid-ocean ridge axis. B. As the seafloor spreads, the lithosphere rises to fill the space between plates. C. Some magma generated during seafloor spreading erupts from submarine volcanoes to form basalt. D. Some magma generated during seafloor spreading spills out onto the surface to produce a new layer of seafloor called gabbro.

Some magma generated during seafloor spreading erupts from submarine volcanoes to form basalt.

Which statement is true about the formation of the Moon?

The Moon formed from debris created when Earth suffered a catastrophic protoplanet collision.

Identify the true statement.Choose one: A. The composition of the giant (Jovian) planets is mainly gas and "ice." B. The only two planets with moons are the Earth and Jupiter. C. Our Sun is the only star we know of that has planets associated with it. D. The Sun accounts for almost 50% of the Solar System's mass.

The composition of the giant (Jovian) planets is mainly gas and "ice."

Identify the statement that is true about the Earth's magnetism.

The magnetic pole is moving at about 55 km per year.

Which of the following is a characteristic of all rocks?

They are a collection of minerals or a body of glass

Categorize processes related to transform boundaries. Sort the following processes those likely to be related to a transform boundary or those likely associated with other boundary types.

Transforms Boundary: earthquakes Other Boundary: divergence, convergence, subduction

Of the choices below, select the one that accurately pairs the feature with the type of plate boundary at which it occurs.

Trenches occur at subduction zones.

This image shows the path of P-waves as they travel through the Earth. Because of physical differences in the mantle (shown in orange) and core (shown in yellow), P-waves refract when they hit the core-mantle boundary.Which of the following is an accurate interpretation of the properties of the outer core and mantle based on P-wave behavior?

Wave velocity is slower in the outer core than in the mantle.

The Himalayas are growing because

a continental plate is colliding with another continental plate there.

The chain of the Hawaiian Islands extends northwest across the Pacific as shown in the figure. The island of Hawaii is the youngest, and the islands get progressively older to the northwest. Plate tectonic theory explains this as

a hot spot currently sitting under Hawaii and the Pacific Plate moving across it in a northwesterly direction.

Physicists have shown that the 92 naturally occurring elements in the universe form during the life cycle of stars. During what stellar process are the very large elements (those heavier than iron) created?

a supernova explosion

Which of the following would form a negative gravity anomaly?

a zone of open space in the lithosphere, such as a cave or cavern

The Big Bang theory states that

all matter and energy in the Universe were once packed into a single point.

Seafloor spreading is driven by volcanic activity that occurs

along mid-ocean ridges.

Which of the following is caused by the interaction of charged particles, magnetic lines of force, and the atmosphere in polar regions?

aurorae

Wegener's theory of continental drift took decades to be accepted

because Wegener couldn't explain how continents moved.

Humans are part of the

biosphere

Use this diagram explaining how marine magnetic anomalies are detected to help you answer the question below. Which of the following variables could influence the width of marine magnetic anomalies on the floor of the ocean?

both A.rate at which the plates are moving away from the mid-ocean ridge B.duration of the magnetic polarity event

Sedimentary rocks form

by grains being cemented together.

The Earth's average density

can be deduced from its volume and gravitational pull.

The rate of plate motion

can be expressed as relative plate velocity, which describes movement of one plate in relation to another plate.

Alfred Wegener proposed the idea of continental drift after he observed evidence from fossils, glacial deposits, and the fit of the continents that suggested all of the continents were once

combined to form a supercontinent (which he termed Pangaea) in the late Paleozoic through the Mesozoic.

Our Solar System

completes one rotation around the center of the Milky Way every 250 million years.

The low-velocity zone (LVZ), found 100 to 200 km beneath oceanic crust, represents

conditions where mantle peridotite partially melts and fills voids between grains.

The lithosphere does not

consist of the crust and lower mantle

Which of the following methods of heat transfer occurs when an increase in temperature creates a decrease in density, causing the warm, less dense material to rise, as shown in this diagram?

convection

Seismic-wave velocity is affected by the

density of the material.

The Earth's magnetic field is created by

flow of liquid iron in Earth's molten outer core

The texture produced when minerals within a metamorphic rock are layered parallel to each other, as shown by the red line, is called

foliation.

The velocities of seismic waves traveling from earthquake foci

generally increase with depth, occasionally making abrupt jumps termed seismic-velocity discontinuities.

The concept placed Earth at the center of the Universe, with the other planets and the Sun revolving around it. The concept placed the Sun as the center, with Earth and the other planets revolving around it.

geocentric; heliocentric

Place each image in the correct box to indicate the Earth material it best represents.

glass: trash bag mineral: crystals melt: lava sediment: rocky terrain rock: boulder

Metamorphic rock

has changed physical characteristics while remaining solid.

The earliest nebulae to form in the Universe were made almost entirely of

hydrogen and helium.

This diagram shows how the tilt of a magnetic needle changes with latitude. Which component of the Earth's magnetic field does this tilt represent?

inclination

Differentiation of large planetesimals and protoplanets

is caused by heat created by the transformation of kinetic energy from collisions into thermal energy.

A crystalline rock

is composed of interlocking minerals that grew together.

Oceanic crust

is covered by a thin blanket of sediment that thickens away from the ridge axis.

The crust

is separated from the mantle by the Moho.

The boundary between the lithosphere and the asthenosphere

is the boundary between rigid mantle and plastic mantle.

The geothermal gradient

is the rate of change in temperature with depth within the Earth.

The Earth is round because

its interior rock is warm enough to flow slowly in response to gravity.

The oceanic crust has distinct layers because of the way it forms. For example, some forms from crystal mush, some from vertical sheets of magma, and some from lava erupted on the seafloor. With these processes in mind, label the layers.

left to right C, A, E ABOVE B, D

In order to answer this question, you'll need to watch the Convergent, Divergent, andTransform topics of the Plate Boundaries Animation. Click here to access the Plate Boundaries Animation. Identify the three types of plate boundaries by labeling the following image. Drag the correct label to the corresponding target.

left to right- A, C, B

Label the image with the features of tectonic plates.

left to right- G, C TOP, D UNDER C, E ABOVE F BELOW IT, B, A, H

Label the features on the illustration of a subduction zone.

left to right- d, c, a above b

Label the diagram of Earth's magnetic field appropriately.

left to right- C,D,A,B

Drag the appropriate labels to the geological features on the map below. Keep in mind that the darker blues represent deeper water.

left to right: b, top a, bottom c, d

Beneath the continents, seismic velocities in the mantle increase with depth because the mantle becomes

less compressible

Marine magnetic anomalies result from seafloor spreading in conjunction with

magnetic polarity reversals.

Which of the following traps cosmic rays and shields life on the Earth from excessive radiation?

magnetosphere

Which of the Earth's layers accounts for most of the volume of the Earth?

mantle

Plate movement is influenced by each of the following EXCEPT

mantle plumes, which are created when hot rock rises up from the deep mantle and creates melting at the base of the lithosphere.

Sort the features of the ocean floor that Harry Hess observed in the development of his seafloor spreading hypothesis.

mid ocean ridge: e, a deep sea trench: c, d seamount chain: b

The two most common gases of the Earth's atmosphere, and their percentages, are

nitrogen (N2) at 78%, and oxygen (O2) at 21%.

This diagram shows the interior structure of the Earth. The inner core is shown as yellow, the outer core as orange, and the mantle as shades of purple. The yellow star marks the focus of an earthquake. Drag and drop the labels to show which type of seismic waves arrive at these three different locations as a result of the earthquake.

pink mantle - Both P-waves and S-waveslight purple mantle - Neither P-waves nor S-waves dark purple - P-waves only

According to current plate tectonics theory,

plates are composed of the crust and the uppermost part of the mantle.

The apparent tendency of the north (or south) magnetic pole to vary in position over time is termed

polar wander.

A petrographic microscope

sends transmitted polarized light through a thin section of rock.

Which of the following pairs of elements composes most of the Earth's crust?

silicon and oxygen

During World War II, the military imaged the seafloor by sending pulses of sound waves down through the water and measuring the time it took for the sound to bounce off the seafloor and return to the receiver. This method is called

sonar

Oceanic lithosphere

that is 10 million years old is cool enough to be denser than the asthenosphere, so it can sink down into or through the asthenosphere.

The reference spheroid does not represent a completely accurate picture of the Earth's gravity because

the equipotential surface of the geoid is not smooth.

Peridotite is

the most abundant rock in the Earth.

The genetic scheme for classifying rocks is based on

the origin of formation.

The global occurrence of earthquakes reveals that

they usually occur on the boundaries of plates or at hot spots.

Label each target on the map below with the name of the appropriate geological feature.

top row left to right d, a, c bottom row left: b

Label the climate belts of Pangaea appropriately.

top to bottom a: desert, c:tropical , b: polar

This figure shows air temperature values in the layers of the Earth's atmosphere. Identify each layer by dragging the labels to the correct spot on the figure.

top to bottom c, d, a, b

Label the polarity chrons with the appropriate title and polarity. Note that some of the chrons contain short-duration subchrons. The boundaries between the chrons are indicated by the heavy black lines. The thickness of layers on this diagram represents the duration of time during which the layer accumulated.

top to bottom: c, a, d, b

This image shows A. how supernovae form. B. two atoms combining during nuclear fusion. C. an example of nuclear fission. D. the formation of electromagnetic radiation.

two atoms combining during nuclear fusion.

The heliocentric model

was supported by observations that planets follow an elliptical orbit.

The heavier elements on the Earth (those with atomic numbers greater than 5)

were formed by stellar nucleosynthesis during the life cycles of older stars and supernovae.

Modern plate tectonic theory was developed in what decade?

1960s

The early view of the Earth's interior layers resembled a hard-boiled egg. Identify the correct labels for this simplified view.

1: crust, 2: mantle, 3: core

The chain of the Hawaiian Islands can be used to calculate the rate of movement of the Pacific Plate over the last few million years. The island of Hawaii currently sits on the hot spot, and is therefore 0 million years old. The island of Kauai used to sit on the hot spot; it is approximately 5.1 million years old and is now approximately 473 km away from the hot spot, to the northwest. Given these parameters, what is the average rate of motion of the Pacific Plate in centimeters per year? (Remember to convert your units properly!)

9 cm per year

Which of the following statements about observing rocks at an outcrop is true?

A hand specimen is a small piece of the outcrop that can be examined closely.

As the map below shows, the oldest seafloor is generally less than 200 million years old. Why?

All oceanic lithosphere eventually gets subducted beneath the continents by the time it is 200 million years old.

Magmas can have a variety of chemical compositions for which of the following reasons?

All answers are correct

Which statement accurately describes the relationship between air pressure and altitude, as illustrated in this figure?

At the top of Mt. Everest, air pressure is 30% of what it is at sea level (altitude of zero).

This image shows a beam of light shining through a half-moon-shaped piece of clear plastic. Light travels at a different velocity through the plastic than it does through the air. Which of the following statements most accurately describe the rays of light and the properties of the clear material?

Because ray B bends away from the boundary, we know that the light ray slowed down when it entered the plastic. A is the reflected ray and B is the refracted ray.

The lithosphere and asthenosphere are known as physically different layers of the Earth because they behave very differently when deformed. Sort the items below into the correct boxes based on characteristics of the lithosphere and asthenosphere.

Lithosphere: mantle and crust, brittle, colder Asthenosphere: mantle only, ductile, warmer

Label the block diagram of the lithosphere appropriately.

left to right: a, b, e, c, d

Place the label that identifies the correct layer of the Earth on the following diagram.

left to right: d, a, c, e, b