Chapter 5

Since humans have been present, the amount of sediments carried by rivers has increased by a factor of about

15 trillon

List three factors that affect the rest of weathering

Mechanical weather climate rock characteristics

what kind of soil is found in the C horizon of a soil profile

Partially weathered parent material

made of equal parts of clay silt and sand

Pedalfer Soil

the air component in soil provides plants with the ____ needed for photosynthesis

carbon dioxide

the inscriptions on marble gravestones become harder and harder to read over time this is caused by

chemical weathering

when's rock is exposed to chemical weathering it changes into one or more new

compound

the slowest type of mass movement, involves the lifting and contracting of soil particles over time

creeps

in a soil profile the ____ layers contain parent material that is hardly weathered at all

deepest

Rock features such as the sculpted pinnacles seen in Bryce Canyon National Park are the result of ____.

differential weathering

one of the most dramatic triggers of sudden mass movements is a

earthquake

oversteepened slopes often lead to____ because the angle of their slope is greater than 49 degrees

erosion

what weathering processes involves the constant freezing and thawing of water

frost wedging

sooo formation be greatest in a flat area in a ____ wet climate areas

hot

chemical weathering is highest in areas that are very

hot and most

Pedalfer soils would most likely be found

in the eastern half of the United States

laterite soil contain high amounts of

iron oxide

human activities such as farming ___ and construction remove vegation from the land and increase the rate of erosion

logging

a landform called a stream valley is the most common result of

mass movement

The process that occurs when physical forces break rock into smaller pieces without changing the rock's chemical composition is called

mechanical weathering

happens when different parts of a rock mass weather at different rates

mechanical weathering

during the process of soil formation _____ decompose dead plant and animals, increasing the amount of organic matter

microorganisms

In general, the largest component of bog soils is

mineral matter

list 3 major components of soil

mineral matter water air

One cause of chemical weathering is the ____ that dissolves in water and then reacts with many common minerals forming oxides

oxygen

large amounts of calcium carbonate are typical of

pedical soil

On a steep slope, erosion is accelerated because there is not enough moisture to sustain sufficient

plant, growth

the main source of organic matter in soil is

plants

Soil that forms on unconsolidated deposits is called

residual soil

A mass movement that involves the sudden movement of a block of material is called a

rockslide

a dense impenetrable layer found in the B horizon of a soil profile

subsoil

Mass movement always leads to landslides

true

Precipitation affects the rate at which nutrients are removed from soil

true

one triggers of mass movements is the pores in sediments filling with

water

the processed called _____ involves physical forces that break rock into smaller pieces

weathering