Weathering
________ is a natural process that causes rock to change, breaks them down, and
causes them to crumble.
Mechanical
chemically.
________ weathering breaks rocks into smaller pieces without changing them
mechanical
When ________ weathering occurs the small pieces of rock that break off are identical
in composition to the original rock.
mechanical
Ice wedging is a type of ________ weathering.
Ice wedging
________ ________ is the freezing and thawing process that breaks apart rocks.
expands
Ice wedging breaks apart rocks because water ________ when it freezes into ice.
Potholes
________ in roads are formed because of ice wedging.
roots
Plant ________ can break apart rocks.
mechanical
When plant roots break apart rocks this is a type of ________ weathering.
Animals ________ can break apart rocks when they tunnel and burrow through the soil.
mechanical
weathering.
When animals tunnel and burrow their way through rock this is a type of ________
Chemical
________ weathering occurs when the chemical composition of rock changes.
carbonic acid
formed.
When water mixes with carbon dioxide from the air or in the soil ________ ________ is
weak
Carbonic acid is a ________ acid.
chemically
Carbonic acid ________ dissolves the rock it comes in contact with.
acid rain
When carbonic acid forms in the atmosphere and falls to the ground as rain we called
this ________ ________.
chemically
Moss
Plants can also ________ break down rocks by producing a plant acid called tannic acid.
________ is a very short green plant that can grow on rocks and break them down chemically.
Oxidation
________ is the effects of chemical changes caused by oxygen.
rust
When iron-containing materials such as steel are oxidized a chemical reaction causes the
material to ________.
oxygen Some rocks can be colored red or orange when iron-bearing minerals in them react with
________.
iron oxide
Even a tiny amount of iron in rock can combine with oxygen and form a reddish
________ ________.
iron oxide
Another name for rust is ________ ________.
rust
Another name for iron oxide is ________.
Soil
________ is a mixture of weathered rock, organic matter, water, and air that supports the
growth of plant life.
leaves Organic matter includes decomposed ________, twigs, roots, and other types of organic
material.
twigs Organic matter includes decomposed leaves, ________ , roots, and other types of organic
material.
roots Organic matter includes decomposed leaves , twigs, ________, and other types of organic
material.
five
There are ________ factors that affect soil formation.
Parent rock
formation.
________ ________, slope of land, climate, time, and organisms are all factors of soil
slope of land Parent rock, ________ _____ ________, climate, time, and organisms are all factors of
soil formation.
climate Parent rock, slope of land, ________, time and organisms are all factors of soil formation.
time
Parent rock, slope of land, climate, ________ and organisms are all factors of soil formation.
organisms
Parent rock, slope of land, climate, time and ________ are all factors of soil formation.
topography
The slope of the land is also called ________.
Topography
________ is the surface features of an area.
little
On steep hillsides soil has ________ chance of developing.
greater In lowland areas where the land is flat soil has a ________ chance of developing.
deep
If rock weathers quickly, ________ soils develop.
shallow If rock weathers slowly, ________ soils develop.
Tropical________ regions where the weather is warm and moist have lots of organic matter in the soil.
Desert ________ regions where the weather is hot and dry have very little organic matter in the soil.
humus When plants and animals die, decomposition by fungi and bacteria form a soil called ________.
Humus ________ helps soil hold water and provides nutrients that plants need to grow.
less
As soils develop, they become ________ like the rock from which they formed.
Lichens ________, organisms that consist of an alga and a fungus living together, can chemically
breakdown rock.
grassland
Some of the best farmland is where ________ used to be.
Erosion ________ is the wearing away and removal of rock or sediment.
gravity Erosion occurs because ________, ice, wind, and water sculpt Earth's surface.
ice
Erosion occurs because gravity, ________, wind, and water sculpt the Earth's surface.
wind
Erosion occurs because gravity, ice, ________, and water sculpt the Earth's surface.
water Erosion occurs because gravity, ice, wind, and ________ sculpt the Earth's surface.
Gravity ________ is a force that pulls every object toward every other object.
center Gravity pulls everything on Earth towards its ________.
downhill
Gravity causes water to flow ________ and rocks to tumble down slopes.
tumble Gravity causes water to flow downhill and rocks to ________ down slopes.
Mass movement
down a slope.
four
________ ________ occurs when gravity alone causes rock or sediment to move
There are ________ types of mass movements.
Creep ________, slump, rock slides, and mudflows are four types of mass movements.
slump Creep, ________, rock slides, and mudflows are four types of mass movements.
rock slides
Creep, slump, ________ ________, and mudflows are four types of mass movements.
mudflows
Creep, slump, rock slides, and ________ are four types of mass movements.
Creep ________ is the name for a process in which sediments move slowly downhill.
freezingCreep is common where ________ and thawing occurs.
thawing
Creep is common where freezing and ________ occurs.
slump A ________ occurs when a mass of rock or sediment moves downhill along a curve surface.
rock slide
During a ________ ________ layers of rock break loose from slopes and slide to the
bottom of the slope.
mudflows
Where heavy rains or melting snow and ice saturate sediments, ________ can develop.
mudflow
A ________ is a mass of wet sediment that flows downhill over the ground surface.
glaciers Over many years, the snow can accumulate to form large, deep masses of ice called ________.
weight When the ice in a glacier becomes thick enough , its own ________ causes it to flow down hill
under the influence of gravity.
erode As glaciers move over Earth's surface, they ________ materials from some areas and deposit
sediment in other areas.
deposit As glaciers move over Earth's surface, they erode materials from some areas and ________
sediment in other areas.
two
There are ________ kinds of glaciers.
Continental
________ glaciers in polar regions cove about ten percent of the Earth and are so large
and thick that tye can bury mountain villages.
Valley ________ glaciers are much smaller and are located in high mountains where the average
temperature isn't warm enough to melt the ice sheets.
erosion Continental and valley glaciers move and cause ________.
cirques In mountains, valley glaciers can remove rock from the mountaintops to form large bowls called
________ and steep peaks called horns.
horns In mountains, valley glaciers can remove rock from the mountaintops to form large bowls called
cirques and steep peaks called ________.
till
The sediment deposited by glacier ice is called ________.
Till
________ is a mixture of different-sized particles of rock, ranging from clay to large boulders.
outwash
size
Sand and gravel deposits laid down by glacier rivers is called ________.
Unlike till, outwash usually consists of particles of rock that are all about the same ________.
deflation
When ________ occurs wind leaves behind particles of rock too heavy to move.
Abrasion
surfaces.
________ is a form of erosion that can make pits in rocks and produce smooth, polished
runoff Water the flows over Earth's surface is called ________.
Sheet ________ erosion occurs when a thin sheet of water carries away loose grains of sediment.
Rills
________ are small channels cut into the sediment at Earth's surface.
gullies When rills widen and deepen they become ________.
Streams
________ are the most important agent of erosion on Earth.
Streams
________ shape more of Earth's surface than ice, wind, or gravity.
Deltas ________ are areas where rivers enter oceans or lakes, the water slows and sediment is
deposited.