chapter 5 study guide

what is mechanical weathering
the physical disintegration of rock, resulting in smaller fragments
what is frost wedging
the mechanical breakup of rock caused by the expansion of freezing water in cracks and crevices
when water freezes its volume
its volume expands by about 9%, exerting a tremendous outward force. this force is great enough to burst water pipes during the winter
which of the following is not associated with mechanical weathering
reactions with oxygen
what is chemical weathering
is the transformation of rock into one or more new compounds
which of the following is the result of chemical weathering
a rock that has been changed into one or more new compounds
the atmospheric gas that form a mild acid when dissolved in water is
carbon dioxide
what would cause the inscription on a marble gravestone to become harder and harder to read overtime
chemical weathering
what climate does chemical weather favor the most
climates with high temperatures and abundant moisture
what are the major components of soil
minerial mater or broken down rock
organic matter or humus which is decayed remains of organisms
a soils texture is determined by
you use categories of clay -silt- and sand in ti soil
the main source of organic matter in soil is
use figure 5-1 to determine what a soil is called if it has 20 percent clay, 60 percent silt, and 20 percent sand
silty loam
what are the proportions of clay, silt, and sand shown at point b in figure 5-1
clay 20 percent
silt 40 percent
sand 40 percent
what are the proportions of clay, silt, and sand shownn at point a in figure 5-1
clay 60 percent
silt 20 percent
sand 20 percent
what are the proportions of clay, silt, and sand shown at point c in figure 5-1
clay 10 percent
silt 20 percent
sand 70 percent
a soil associated with the hot and wet tropics is
pedalfer soils contain high amounts of
iron oxide and aluminum- rich clays
the process responsible for moving material downslope under the influence of gravity is called
mass movements
what is the force behind mass movement
a mass movement that involves the sudden movement of a block of material along a flat, inclined surface is called a
which of these factors affects the rate of weathering
all of the above
why can the removal of vegetation trigger mass movements
the plant roots bind the soil and regolith together
in the process of _______, water freezes and expands, enlarging cracks in rocks
frost wedging
a large pile of debris that forms at the base of a slope is called
what is the most inportant agent of chemical weathering
what is regolith
layer of rock and minerial fragments, which covers nearly all of the earths land surface
the force that drives mass movements is
what is the content in the soil type pedocal
abundant calcite or calcium carbonate and are typically light gray-brown
what is the location and content of the soil type laterite
found in hot, wet tropical areas. iron oxides and aluminum oxides are present
one of the most dramatic triggers of sudden mass movements is a(n)
________, the slowest type of mass movement, involves the lifting and contracting of soil particles over time
what are the three factors that affect the rate of weathering
mechanical weathering, rock characteristics, and climate
how are soils classified based on texture
you use the percentage of clay, silt, and sand
explain the three processes that break rocks into smaller pieces during mechanical weathering
frost wedging, unloading, and biological activity