GEOL 1405 Exam 2

Sinkholes usually form when the ground becomes wet and things sink into them after a big rainstorm T/F

False

There have never been any caldera eruptions in the U.S. and probably won't be in the future. True/Flase

False

Which of the following human activities can DECREASE the incidence of mass wasting?

Improving drainage from the slope

Which of the following describes the tsunami in Lituya Bay, Alaska in 1958?

M 7.7 earthquake triggered a massive landslide, which fell into the water and caused water to surge over 500 m above the normal water level.

Growing plants on a slope will always make it more stable because plant roots add strength and cohesion to the soil True/False

True

Mauna Loa in Hawaii is an example of a shield volcano built over a hotspot. True/Flase

True

The distinct layers of a soil are called soil horizons T/F

True

The type of mass wasting process that occurs depends on many different factors including the steepness of the slop and the type of material involved True/False

True

Weathering is the physical and chemical breakdown of rocks into smaller pieces and is involved in soil development T/F

True

Why don't boats in the open ocean notice a tsunami approaching?

Tsunamis are too small in amplitude in the open ocean and the distance between crests is too large for boats to notice their passing.

Why do sailors rarely notice a tsunami passing in the ocean?

Tsunamis are too small in amplitude in the open ocean, and the distance between crests is too large to notice its passing

Which of the following is NOT a way in which water contributes to slop failure?

Water adds cohesion between the grains of the soil causing it to become unstable

Magma begins to form if rocks close to their melting temperature and the pressure from above is decreased in the process called

decompression melting

Which of the following describes a slump?

Blocks of rock break off and move together, sliding along a curved path

A tsunami is a wave in the ocean

.usually caused by earthquakes

What is subsidence?

A sinking of the ground surface

What is the definition of soil according to a soil scientist?

Any solid earth material that has been altered by physical, chemical, and organic processes so that it can support rooted plants

Where is the majority of lava extruded

At divergent plate boundaries

Which of the following regions has the LEAST risk from tsunamis?

Atlantic coast of the U.S.

Which of the following magma types will usually flow the fastest?

Basaltic

In order of increasing silica content, the three major types of magma are

Basaltic, andesitic, rhyolitic

Which is NOT a location where volcanoes are found?

Central United States

What is the most important soil particle that characterizes expansive soils?

Clay Minerals

What is the correct order of soil grain size from smallest to largest?

Clay, silt, sand, gravel

Which of the following does NOT cause ground subsidence?

Creation of permanently frozen ground where no thawing ever occurs

How is the stability of a slope assessed?

Determining the relationship between driving forces and resisting forces

Which of the following is not usually caused by land subsidence or soil volume change?

Disease

What is mass wasting?

Downslope movement of rock, soil, and sediment

A single tsunami produces one wave, either a local tsunami or a distant tsunami. True/False

False

Karst topography is a very rare type of landscape seen in many areas of the United States T/F

False

Where does the majority of soil originate from?

It comes from weathered rock

Does adding vegetation to a slope make it more or less stable?

It depends on the slope, adding vegetation could make the slope either more or less stable

Would adding mass to the top of a slope in the form of houses of buildings make the mass more or less likely to slide?

It would make it more likely to slide because the houses add weight to the slope making it more unstable

Which of the following describes the tsunami in Indonesia in 2004?

M 9 earthquake triggered a 10 m tsunami, which was the deadliest tsunami ever, killing more than 200,000 people in several countries.

What is the difference between magma and lava?

Magma is found below the Earth's surface, lava is found on the Earth's surface

Why are so many volcanoes found on the Ring of Fire around the margin of the Pacific Ocean?

Many Subduction Zone occur there

Which shorelines are at greatest risk for tsunamis?

Near subduction zones

How good of an indicator is soil color in categorizing the soil horizon?

Reasonable good, Sometimes color can be misleading, but usually it can give you a good idea

Which of the following environments is NOT susceptible to mass wasting?

Relatively flat-lying area

Which of the following is the most rapid form of mass wasting?

Rock fall

Which of the following involves downslope movement of a coherent, usually large block of earth material along a planar surface?

Rock slide

Mt. St. Helens in Washington is an example of which type of volcano?

Stratovolcano

Which of the following is FALSE about magma?

Tectonic plates move around on an underground ocean of magma

Why don't earthquakes on transform faults trigger tsunamis?

The earthquakes don't vertically displace the water in the ocean.

What is runup?

The farthest horizontal and vertical distance that tsunami waves move inland

What happens as a tsunami nears land?

The height of the waves increases due to a decrease in both water depth and tsunami velocity.

Which of the following natural hazards is Not caused by volcanoes?

Tornadoes

In which of the following tectonic plate settings are volcanoes typically NOT found?

Transform fault

What is the most common driving force of landslides?

Weight