Weathering is the breakdown of rocks into smaller pieces through various processes like plant growth, water, freezing and thawing. Erosion is the movement of weathered material from one location to another by forces like water, wind, glaciers and gravity. Deposition is the placement of eroded pieces of Earth's surface in a new location, like sand dunes formed by wind or new islands created from sediment deposited by rivers in the ocean. Over time, weathering, erosion and deposition break down bedrock into soil and shape the landforms on Earth's surface.

1. February 2013
What are
weathering
and
?erosion

3. Weathering by
plants

4. Landforms are the solid features
found on Earth`s surface, like:
mountains valleys
Landforms change constantly.
For this to happen, rock in
landforms must first break
.apart

7. Weathering is any process that
breaks rocks into smaller pieces.
Weathering changes
centuries less than a year

10. plants sometimes cause
weathering. Their roots can grow
into cracks in rocks. As the roots
get bigger, they can split and
.break up the rocks

12. Weathering by
water

13. Water can cause weathering.
Water changes the minerals
1
in some rocks. The rocks become
weakened and may begin to
.break apart

14. 2
Water freezes and thaws. It
can get into cracks in rocks.
When water freezes, it expands,
or grows larger.
The ice pushes against the sides
of the cracks. Over the years,
. the rocks may break apart

16. Erosion by
water

17. Weathered material
stays in place is picked up and
carried to other
places
Erosion is the movement of
.weathered material

19. Water can cause
Erosion
Rainwater can carry away soil
from farm fields.
Waves cause erosion along
shorelines.
Rivers carry bits of rock
from one place to another.
Sand and mud flow over a
.river`s banks during a flood

23. Glacier can cause
Erosion
Glaciers are huge bodies of ice
and snow that moves over
Earth`s crust.
As a glacier moves, it wears away
bits of rock and soil and carries
.them off

24. Glacier erosion

26. Erosion by
wind

27. Erosion by wind is common in dry
.regions, such as deserts

28. Wind can carry dry sand and soil
to other places. Few tall plants
grow in deserts. This means there
is little to stop the particles of sand
.and soil from blowing around

29. Sand and soil particles can cause
weathering when blown by the
wind. The particles bump into
rocks and breaks off tiny grains.
Over time, more grains are broken off.
.The rocks slowly change

31. Other causes
of Erosion
Gravity Living things

32. 1
Gravity pulls rocks and soil
downhill. The material moves
slowly if the slope is gentle. It
.can move quickly on steep slopes

33. Mudflow is the quick movement
of very wet soil.
Rockslide is the quick movement
.of rocks down a slope

34. mudflow

35. rockslide

36. 2
Ground squirrels tunnel
through soil. The tunneling allows
water and air to move into the
.ground. this causes erosion

37. Gravity pulls loose
rock and soil downhill
.in a rockslide

38. Deposition

39. The rock and soil that erosion
carries away must go someplace.
Deposition is the placing of
pieces of Earth`s surface in a
.new place

40. New islands can form as a result
of deposition.
When rriivveerrss
carry rock and bits
of soil to the ocean.
These particles build up over
time and can form islands off
.the coast

41. Wind
can blow sand into
mounds.
.These mounds sand dunes

42. Desert winds have formed
.many sand dunes

43. Weathering,
erosion, & soil

44. Why soils are not
alike everywhere in
?the world

45. 1
2
3
Soil is made up of tiny pieces of
rock, air, water, and humus.
The tiny pieces of rock come
from larger rocks that have broken
up.
Rocks are broken up and moved
about through weathering and
.erosion

46. 4
5
6
Small plants sprout in the rock
and eventually die.
The remains of these plants
break down and form humus.
Soil develops from different
.kinds of rocks and plants