Chapter 9 Weathering and Mass Movement
Which of the following is an example of ways in which global climate change may specifically hasten mass movement?
Declining forests from disease and drought will increase slope instability and mass movement events.
The maximum angle at which soil, sediment, and rock will remain without moving downslope (e.g., a stable slope) is the
angle of repose.
Which of the following human activities can contribute to mass movement?
any human disturbance of a slope, including road cuts, surface mining, and development
Salt-crystal growth (salt weathering) is prevalent in which climate type?
arid
Chemical weathering processes are particularly effective on limestone landscapes, forming
karst topography.
The solid rock from which regolith and soil develop is
bedrock.
Extensive landscapes formed by the dissolution of limestone and other carbonate rock and characterized by pitted, bumpy surface topography, poor surface drainage, and well developed solutions channels are known as
karst topography.
Hundreds of people in northeastern Afghanistan were killed when this sudden rapid movement of an unsaturated cohesive mass of regolith or bedrock occurred, an example of
landslide.
The sudden rapid movement of an unsaturated cohesive mass of regolith or bedrock is a
landslide.
Frost wedging is an example of ________ weathering processes.
only physical
Which of the following is not a denudation process?
orogeny
Rust, formed by the reaction of iron and oxygen in the presence of water, is an example of
oxidation.
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 down and disintegrated without any chemical alterations, the process in operation is
physical weathering.
Which of the following weathering processes does not involve water?
pressure-release jointing
A niche in sandstone, such as that in Arizona's Canyon de Chelly, is indicative of which weathering process?
salt-crystal growth
Many of the Native American dwellings at Mesa Verde and elsewhere in the western United States are located under overhangs that form along the contact between permeable and impermeable rock layers. These overhangs (niches) were primarily created by what process?
salt-crystal growth
Which of the following is not a class of mass movement?
slip
A slow persistent mass movement of surface soil is called
soil creep
A slope whose strength exceeds the combined force of gravity and the denudation process is
stable.
A slope is ________ if its strength exceed denudation processes and ________ if its materials are weaker than denudation processes.
stable; unstable
Which of the following are examples of dripstones?
stalactites
Which of the following is not exogenic in nature?
tectonic uplift
Hydration involves
the addition of water with little chemical change.
________ is a steep scarp or cliff whose presence indicates an outcrop of resistant rock.
Free face
Which of the following is correct regarding joints?
Joints are fractures in rock that occur without displacement on either side.
Any large cave formed by chemical processes is a
cavern.
When rock is broken down and disintegrated in the presence of water and with chemical alterations to the rock, the process in operation is
chemical weathering.
A mass of falling and tumbling rock, debris, and soil leveling at a high velocity owing to the presence of ice or water is a
debris avalanche.
When pressure is removed from overlying rock, the pressure of deep burial is relieved, initiating pressure-release jointing. The joints then separate into curved slabs. This is known as
exfoliation.
Physical and chemical weathering processes typically occur along the ________ of a slope.
free face
The angle of repose represent a balance between the driving force and resisting force. Which of the following is the resisting force?
friction
If material is to move down slope, it must overcome the force of
friction, cohesion of particles, and inertial resistance.
Plants are important to the development of karst formation primarily because
they supply organic acids that enhance the dissolution process.
A slope whose materials are weaker than the combined force of gravity and the denudation process is
unstable.
Which of the following are the principal active agents involved in chemical weathering?
water, oxygen, carbon dioxide