geo 2

Question 1

The Columbia Plateau in Washington and Oregon is ________.

Answer 1

A large igneous province formed by extensive basaltic lava flows.

Question 2

What is the largest known volcano in the Solar System?

Answer 2

Olympus Mons on Mars.

Question 3

How is the recent (geologically) volcanic activity in Yellowstone National Park related to plate tectonics?

Answer 3

It is caused by a mantle hotspot, independent of plate boundaries.

Question 4

Which type of basaltic lava flow has its surface covered with sharp-edged, angular blocks and rubble?

Answer 4

A’a lava.

Question 5

Which type of basaltic lava flow has a fairly smooth, unfragmented, ropy surface?

Answer 5

Pahoehoe lava.

Question 6

The finely divided, red, brown, and yellow soil-coloring minerals originate by what process?

Answer 6

Chemical weathering, particularly oxidation.

Question 7

What processes are involved in mechanical weathering?

Answer 7

Frost wedging, exfoliation, thermal expansion, biological activity, and abrasion.

Question 8

Which terms best describe those processes that move weathered rock materials and soils downslope?

Answer 8

Mass wasting or mass movement.

Question 9

Describe the characteristic processes involved in soil erosion.

Answer 9

Detachment, transport, and deposition by wind, water, or gravity

Question 10

What happens when water fills a crack in a rock and undergoes cycles of freezing and melting?

Answer 10

The crack expands due to frost wedging, eventually breaking the rock apart

Question 11

In which area are pedocal soils most likely to be found?

Answer 11

: In dry, arid, and semi-arid climates.

Question 12

In correct order from the center outward, Earth includes which units?

Answer 12

Inner core, outer core, mantle, crust.

Question 13

________ rocks always originate at the surface of the solid Earth.
A) Metamorphic B) Secondary C) Sedimentary D) Igneous

Answer 13

C) Sedimentary.

Question 14

The ________ proposes that the bodies of our solar system formed at essentially the same time from a rotating cloud of gases and dust.

Answer 14

Nebular hypothesis.

Question 15

The ________ forms the relatively cool, brittle plates of plate tectonics.

Answer 15

Lithosphere.

Question 16

Are Mount St. Helens and the other Cascade volcanoes young or old, active or inactive, and what type of margin produces them?

Answer 16

They are young, active, and formed at a convergent plate boundary (subduction zone).

Question 17

What are the major pieces of evidence supporting the theory of plate tectonics?

Answer 17

Fossil distribution, seafloor spreading, paleomagnetism, earthquake patterns, and GPS measurements.

Question 18

The temperature below which a magnetic material can retain a permanent magnetization is called the ________.

Answer 18

Curie temperature.

Question 19

Where is the top of the asthenosphere closest to Earth’s surface?

Answer 19

At mid-ocean ridges.

Question 20

Which diseases are linked directly to prolonged inhalation of asbestos dust?

Answer 20

Lung cancer, asbestosis, and mesothelioma.

Question 21

The strong tendency of certain minerals to break along smooth, parallel planes is known as ________.

Answer 21

Cleavage.

Question 22

Which group of minerals are the most abundant in the Earth’s crust?

Answer 22

Silicates.

Question 23

Which igneous rocks exhibit aphanitic texture?

Answer 23

Basalt, andesite, rhyolite.

Question 24

Changing the composition of magma by incorporating surrounding host rock is known as ________.

Answer 24

Assimilation.

Question 25

A ________ texture would be most unlikely to occur in an extrusive igneous rock

Answer 25

Pegmatitic texture.

Question 26

What factors influence the melting temperatures and viscosity of magmas?

Answer 26

Temperature, silica content, and water content.

Question 27

________ destroyed the city of St. Pierre, Martinique in 1902.

Answer 27

A pyroclastic flow from Mount Pelée.

Question 28

A ________ is an intrusive, igneous rock body that is tabular and concordant.

Answer 28

Sill.

Question 29

Under similar warm, moist climatic conditions, why would basalt and gabbro generally have higher chemical weathering rates than rhyolite and granite?

Answer 29

Because basalt and gabbro contain more mafic minerals, which weather more quickly than felsic minerals.

Question 30

Lateritic soils form under what climatic conditions?

Answer 30

Warm and humid tropical climates.

Question 31

Compared to the age of Earth accepted as correct today, how did 17th and 18th century proponents of catastrophism envision the Earth's age?

Answer 31

They believed Earth was only a few thousand years old.

Question 32

________ is often paraphrased as "the present is the key to the past."

Answer 32

Uniformitarianism.

Question 33

Why is so much basaltic magma erupted along mid-ocean ridges?

Answer 33

Due to decompression melting as the lithosphere pulls apart.

Question 34

What are the lightest or least massive of the basic atomic particles?

Answer 34

Electrons.

Question 35

________ is composed mainly of ferromagnesian minerals.

Answer 35

Peridotite.

Question 36

Which of the following statements concerning humus is not true? A) consists of decaying and partly decayed leaves and other plant materials B) is readily leached from the B horizon in weakly acidic, soil solutions C) is typically found above the B soil horizon D) is less abundant in wet, tropical, forested areas than in temperate, forested areas

Answer 36

B) is readily leached from the B horizon in weakly acidic, soil solutions.

Question 37

________ was the highly influential, ancient Greek philosopher noted for his writings and teachings on natural philosophy and on the workings of Earth.

Answer 37

Aristotle.

Question 38

Early results of the Deep Sea Drilling Project clearly justified the conclusion that ________.

Answer 38

The ocean floor is younger near mid-ocean ridges and older further away, supporting seafloor spreading.

Question 39

Which of the following will react readily with acids such as hydrochloric? A) talc B) calcite C) quartz D) diamond

Answer 39

B) Calcite.

Question 40

Which igneous rock or magma has the lowest silica (SiO₂) content?

Answer 40

Ultramafic rocks, such as peridotite.

Question 41

Which statement about the May, 1980, eruption of Mount St. Helens is false? A) The most powerful explosive event was preceded by a massive landslide. B) Mudflows accompanied the major eruptive events. C) During the eruptive period, the mountain peak was substantially built up by new lava flows and pyroclastic debris. D) Plumes of ash rose high into the atmosphere during the major eruptive events.

Answer 41

C) During the eruptive period, the mountain peak was substantially built up by new lava flows and pyroclastic debris.

Question 42

Which term describes a soil formed by weathering of the underlying bedrock?

Answer 42

Residual soil.

Question 43

What is the difference between magma and basalt?

Answer 43

Magma is molten rock beneath Earth's surface, while basalt is a solidified extrusive igneous rock formed from magma.