Geo Ch 10

The disintegration and dissolving of surface and subsurface rock is called

weathering

Which of the following is a type of chemical weathering process?

hydrolysis

All unit movement of materials propelled and controlled by gravity are referred to as

mass movements or mass wasting.

Physical weathering is greatest under conditions of

temperatures that reach below freezing.

The rate at which rocks weather depends upon

the climate of an area, the type of rock, the amount of vegetation in an area.

One side of a sand dune is typically steeper than the other side. The slope of the steepest is controlled by the angle of repose for sand—which has a value that is typical for most materials. This angle is about ________.

34 degrees

Which of the following countries is noted for its spectacular tower karst?

China

The steepness of a slope of loose material at rest is the

angle of repose.

If you have ever played on a beach and made a sand castle, you used wet sand rather than dry sand. You did this because the ________ of wet sand is greater than that of dry sand.

angle of repose and cohesiveness

Exfoliation occurs because

overlying rock is removed, thereby allowing the underlying rock mass to expand.

The yellow-red stains that occur on some rock surfaces are the result of ________, which is a form of ________ weathering.

oxidation; chemical

When rock is broken and disintegrated without dissolving, the process in operation is

physical weathering.

Uplift of the landscape creates ________ energy which is converted to ________ energy when materials begin to move downslope.

potential; kinetic

The dramatic domes and arch-shaped features found in granitic mountain masses result from

pressure-release jointing, exfoliation, and sheeting.

A persistent mass movement of surface soil is called a

soil creep.

Other than the rock itself, the most important chemical substance needed for the majority of weathering processes is

water

Hydrolysis involves

water chemically combining with minerals.

Which of the following are the principal active agents involved in chemical weathering?

water, oxygen, carbon dioxide

Which type of weathering is limited to arid environments?

salt-crystal growth

In 1973, part of the flat ground on which a subdivision was located became saturated and began to flow toward the Saint Lawrence River at speeds of up to 26 kmph (16 mph). The ground that flowed consisted of silts and clays—not large, rocky regolith. What type of mass wasting event was this?

Earth flow

The dynamic equilibrium model refers to

a balancing act between tectonic uplift and rates of reduction in a given landscape.

Movement at the geomorphic threshold signals

a conversion of potential energy to kinetic energy.

After a threshold is crossed, the landscape

adjusts to a new equilibrium condition.

Karst topography is formed primarily by

carbonic acid solution.

The weathering of limestone can create circular depressions known as

caverns

If material is to move downslope, it must overcome the force of

friction, the cohesion of particles to each other, inertial resistance of the material.

The fact that water expands as much as 9 percent of its volume as it freezes is the basis of

frost wedging.

The science that specifically studies the origin, evolution, form, and spatial distribution of landforms is

geomorphology.

Chemical weathering is greatest under conditions of

higher mean annual rainfall and temperatures.

In which of the following climates would the subsurface line of contact between weathered and unweathered materials be at the greatest depth?

hot and wet

A translational slide involves

movement of surface material along a planar surface.

In the Northern hemisphere mid-latitudes, slopes that face ________ have more trees on them because ________.

north; they are more moist