Geology Exam 1

What is the central area (A) called? What is the composition of A? What is the composition of the material in B?

- The sun - Dust Particles - Ice Particles

On the diagram below, show relative motion across the active transform fault with half arrows and plate motion relative to the ridge axis with full arrows.

- There are 2 plates in action

Up to what elevation can you live without needing supplemental oxygen?

5.5 km

Which of the following best describes the geocentric model of the Universe?

The Earth is the center of the Universe, and the stars and planets rotate around it.

A rock that forms from molten material is called _________ whereas a rock that forms from a preexisting rock and undergoes changes in heat and pressure is called ________.

igneous; metamorphic

What percentage of the Earth's radius does the thickness of the crust represent?

no more than 1%

Which layer is responsible for the magnetic field?

outer core

Arc volcanoes form above the __________ plate.

overriding

Marine magnetic anomalies are _________________.

positive and negative anomalies in the upper layer of ocean crust

Researchers assumed that continents __________ and that Earth's magnetic poles actually moved long distances over time.

remained in fixed positions

This image shows a cross section of the Atlantic Ocean floor. Label the principal bathymetric provinces.

C- Continental Shelf A- abyssal plain B- Mid-ocean ridge D- Ridge Axis

Imagine that you are a Greek philosopher living 2,000 years ago. If you were to lecture on the structure of the Universe to students, which of the following statements would help your students distinguish between stars and planets?

- Stars appear to revolve around a fixed point. - Planets move in complex paths independent of stars.

Based on the geothermal gradient graph, what can be said about temperature and pressure within the Earth?

- Temperature increases with depth. - At greater depths, the pressure is higher.

Using the earthquake location map below, select all of the locations that represent plate boundaries.

1,2,4,6

What is the approximate distance from Earth to the Sun?

150,000,000 kilometers

What percentage of the lithosphere is continental, and what percentage is oceanic?

30% continental, 70% oceanic

How does a planet differ from a protoplanet?

A protoplanet is a large, nonspherical body smaller than a planet

Describe the process by which oceanic lithospheric mantle forms.

As newly formed oceanic crust moves away from the ridge axis, the crust and the mantle directly beneath it gradually lose heat to the ocean above, forming lithospheric mantle.

Label the key bathymetric features in this diagram of a volcanic arc.

A- Seamount B- Trench C- Volcanic Arc D- Magma

How does the crust of a continental shelf differ from the crust in a continent's interior?

Continental shelf crust is generally thinner and below sea level.

How are fracture zones oriented relative to the axis of a mid-ocean ridge?

Fracture zones run perpendicular to a mid-ocean ridge axis.

How did Wegener use a map of fossil distribution and rock types to support his hypothesis of continental drift?

He found similar rocks and fossils on continents that are currently separated by ocean and deduced that the continents must have been connected at some point.

Why do astronomers use light-years to define distances between stars?

It is a convenient way to measure vast distances.

How can glass be distinguished from a mineral?

Minerals have a crystal form; glass does not because its atoms are not arranged in an orderly manner.

Can the pattern of glacial striations be explained if continents have always been in their present-day locations?

No, because glacial ice moves toward coastlines, as many of the striations indicate, not toward the middle of continents

Could a planet like Earth have formed around a first-generation star?

No. First-generation stars formed from nebulae that had only elements 1 through 5 on the periodic table, whereas Earth's core is composed primarily of iron (26 on the periodic table).

Why are abyssal plains deeper than mid-ocean ridges?

Older lithosphere sinks down into the asthenosphere because it is thicker, colder, and denser than younger lithosphere.

How does a protoplanet differ from a moon?

Protoplanets orbit the Sun; moons orbit planets.

How do sediments differ from melts?

Sediments are loose, unconsolidated grains; melts are liquids that were derived from solids.

Which of the following best describes the helioentric model of the Universe?

The Sun is the center of the Solar System, and the planets orbit around it.

What is the link between the observation that the Universe is expanding and the Big Bang theory?

The discovery that all objects in the Universe are spreading apart led to the idea that everything must have been together at some point and then began to expand. This idea is known as the Big Bang theory.

What is the inclined band of deep earthquakes called?

Wadati-Benioff zone

How does Earth's inner core differ from its outer core?

The inner core is solid; the outer core is liquid.

How does the lithosphere differ from the asthenosphere?

The lithosphere is rigid; the asthenosphere is plastic.

Does the rock composition differ between point X and point Y? Do the temperatures at these points differ?

The rock composition is the same, but the temperature is different, with point X being cooler than point Y.

How did Wegener use this map to justify his continental-drift hypothesis?

Wegener speculated that the distribution of late-Paleozoic sedimentary environments defined climate belts on Pangaea and therefore the position of the continents.

Why did most geologists of Wegener's day reject his hypothesis?

Wegner could not explain how or why continents were moving.

Where does melting occur at a convergent plate boundary?

Where does melting occur at a convergent plate boundary?

Does the crab nebula contain any uranium?

Yes, because the Crab Nebula represents a supernova explosion whose extreme high temperatures allowed for the formation of heavier elements.

A material that can exist as a gas on the Earth's surface is called

a volatile.

Is the lithospheric mantle thicker beneath a mid-ocean ridge or beneath a continental shelf?

beneath a continental shelf

Are earthquakes located in the overriding plate or the downgoing plate?

both overriding and downgoing plates

In what direction do the planets revolve around the Sun?

counterclockwise

What does the solar wind consist of?

dangerous radiation

Which of the following is not one of Earth's domains?

the Moon

What visible evidence illustrates the interaction between Earth's magnetic field and solar wind?

the aurora borealis

Which of the following best describes the habitable zone?

the distance from the Sun where temperatures range between 0°C (freezing) to 100°C (boiling)

An apparent polar-wander path for a continent represents ______________.

the movement of a continent relative to fixed magnetic poles