Download Match the weathering types with the appropriate definition

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Match the weathering types with the appropriate definition.
Weathering
type
A. Frost
wedging
B. Salt
wedging
C. Exfoliation
D. Abrasion
E. Thermal
expansion
F. Chemical
reaction
G. Dissolution
H. Biological
Answer
(letter)
G
D
E
A
C
F
H
B
Definition
1. Rocks can dissolve in water (especially
acidic water) from rainfall, rivers, and other
sources.
2. Mechanical scraping of rocks by friction
due to small particles which are
transported by wind, water, glaciers, or
gravity.
3. Rocks expand when they are heated (often
during the daytime) and contract when they
are cooled (at night), which puts stress on
the rock and causes it to breakdown.
4. Water enters cracks in the rock and when
the water freezers it expands and causes
the cracks in the rock to grow.
5. Rocks which are buried are under pressure
due to the material on top of them. When
the material on top is removed, the
pressure is released and the rocks and
fracture parallel to the surface, causing
sheets of rock to be released.
6. Rocks can undergo chemical changes,
such as rust, which cause them to
breakdown.
7. Microorganisms and plants can enter the
cracks in rocks and grow, causing the
cracks to expand.
8. Salts dissolved in water enter cracks in the
rock with the water. When the water
evaporates or flows out of the rock, the
salts grow as solid crystals, which cause
the cracks in the rock to grow.
Fill in the blanks using the words in the box below. Words will not be repeated,
and you will not use all of the words.
Physical weathering processes cause rocks to break down without a chemical
reaction occurring. One of the major physical weathering processes is abrasion,
during which rocks are broken down by mechanical scraping with small moving
particles in the air or water. Another physical weathering process is thermal
expansion, which occurs when rocks are heated and expand in size, then cooled and
contract in size. The repeated changes in size cause stress in the rocks, which
causes cracks. When rocks are formed underneath the surface of the earth, they are
under pressure from the material on top of them. When this material is removed, the
pressure is also removed and exfoliation occurs, causing the rock to fracture and
come off in sheets. Chemical weathering processes involve chemical changes. For
example, many rocks dissolve in water from rain, rivers, or other sources. Rocks are
especially soluble in acidic water. Weathering due to chemical reaction, such as rust,
can also cause rocks to weather.
Weathering can also occur when materials enter existing cracks in rocks. For
example, in frost wedging water enters the cracks in rocks where it freezes and
expands, causing the cracks to expand. Water can also evaporate and leave behind
salt crystals, which is called salt wedging. Biological weathering processes all involve
living organisms, for example, microorganisms or plant roots can become wedged in
the cracks in rocks and grow, causing the cracks to grow as well.
removed
reaction
physical
expands
sheets
acidic
roots
dissolve
heated
biological
wedging
chemical
weathering
rivers
cracks
frost
exfoliation
crystals
holes
pressure
contract
dead
abrasion
living
basic