Ch.16 online quiz

During the chemical weathering of feldspar to form kaolinite, water is:

consumed

When ground becomes saturated with water, the internal friction between the particles:

decrease

The soil layer comprising slightly altered bedrock broken and decayed, mixed with clay produced by chemical weathering, is called:

C-horizon.

Mass wasting is most likely to occur when the angle of a slope is ______ the angle of repose.

greater than

How fast do debris avalanches travel?

greater than 5 km/h

The Vaiont, Italy disaster of 1963 had warning signs, including:

steep layers of limestone and shale above the reservoir. b. scar of ancient slide on the valley wall above the reservoir. c. a small rockslide in the same wall three years earlier.

What is the nature of movement in mass wasting?

sliding flowing

Leaching is a process by which some materials are removed from soil by:

water chemically weathering and removing.

A mass of unconsolidated material slides down-slope as a unit, leaving a scar at its source. This is called:

slump.

Fastest movements occur when material is composed of:

solids-air mixture.

Type of movement in which water in surface soil layers freezes and thaws, causing the soil to ooze downhill:

solifluction.

Increasing acidity of soil:

speeds up chemical weathering

As the mineral feldspar is chemically weathered to kaolinite:

-some ions from the feldspar go into solution. - some water is added to the mineral. -structure of the mineral changes.

How fast is soil creep?

1 to 10 mm/yr

Approximately how many cubic meters of rock and soil slid during the Gros Ventre slide of 1925?

2 million cubic meters

In the ferric iron of hematite, iron atoms have lost ____ electrons.

3

____________ is an attractive force between particles of a solid material that are close together.

Cohesion

What is the difference between an earthflow and a debris flow?

Earthflows are mostly made up of fine-grained unconsolidated material, and debris flows consist of unconsolidated rock fragments and mud.

What is the relation between earthquakes and landslides?

Earthquakes sometimes trigger landslides.

How does the steepness of a slope affect mass wasting?

The steeper the slope, the more likely mass wasting will occur.

A substance that releases hydrogen ions (H+) to a solution is called a(n):

acid

Natural zones of weakness that allow weathering to penetrate rocks are called:

bedding planes. joints. cleavage planes.

Solifluction occurs in:

cold regions.

Which of the following conditions impedes (slows) chemical weathering?

cold temperatures

What was the mass wasting event at Mount Huascaran, Peru, in 1970, which killed thousands?

debris avalanche

Which of the following mass movements is the fastest?

debris avalanche

What is a triggering event for mass wasting?

earthquake b. over-steepening of slope c. heavy rainfall

Which of the following involves the set of processes by which soil and rock are loosened and moved downhill (or downwind)?

erosion

Which mineral is most abundant in Earth's crust?

feldspar

Mass wasting is caused by:

gravity

Pyroxene exposed at the Earth's surface weathers to form which iron oxide mineral?

hematite

Which of the following can lead to oversteepening of a slope?

human activities natural erosional processes

Which of the following processes is an example of chemical weathering?

hydrolysis of feldspar

What are the effects of increased temperature on weathering?

increased chemical and decreased physical weathering

As a rock breaks into smaller pieces, the surface area:

increases.

What is the greatest source of carbon and sulfur for atmospheric gases?

industrial pollution

Which of the following forms of iron is the most stable at the Earth's surface?

iron oxide

Red soils of Georgia and other areas are colored by:

iron oxides.

Soil moisture ____________ falling rain.

is more acidic than

Mudflows comprising wet pyroclastic material are called:

lahar.

The highest angle of repose of unconsolidated sediment is for __________ pieces.

large, flat, angular

Carbon dioxide makes up _______ of the Earth's atmosphere.

less than 0.1 percent

Which of the following rock types dissolves most rapidly in a hot, humid climate?

limestone

During an earthquake, water-saturated sand can behave like a liquid, a process called:

liquefaction.

The process by which large chunks of material collapse and move down-slope is:

mass wasting

Mass movement classification is based on interaction of:

nature of moving material, velocity of movement, and nature of movement.

Mass movement is influenced by:

nature of slope material. b. water content. c. steepness of slope. d. all of the above.

Which of the following minerals is LEAST stable at the Earth's surface?

olivine

Black color of a soil is generally a result of high ___________ content.

organic matter

Ancient soils preserved as a rock layer in the rock record are called:

paleosols.

Tree roots growing in cracks in rock are an example of

physical weathering

Frost wedging, the widening of cracks in a rock due to the expansion of freezing water, is an example of:

physical weathering.

Which of the following minerals has a low solubility and therefore is least susceptible to chemical weathering?

quartz

The relationship of shear strength and shear stress to mass movement: mass movement is more likely to occur if

shear strength decreases and shear stress increases.

Damp sand has a higher angle of repose than dry sand because of:

surface tension.

Which of the following is a factor controlling rate of weathering?

the climate

After the Vaiont Dam disaster, it was determined that:

the debris slide was inevitable; disaster would have been minimized if the dam had not been built.

The five factors that affect soil formation are bedrock composition, climate, _________, organisms, and time.

topography

Loose, uncemented geologic material is said to be:

unconsolidated

Rate of chemical weathering is dependent on stability of a mineral in the presence of: _____________.

water.