Download Erosion and Weathering ppt

• 1. The earth is the
only living planet…
* Continents –
landmasses above
water on earth
IV. External Forces Shaping
the Earth
a. Weathering and erosion alter
the surface of the earth
Weathering
Weathering
• physical and chemical processes that
change the characteristics of rock on or
near the earth’s surface
v. Mechanical Weathering –
processes that break rock into
smaller pieces (doesn’t change
the composition of rock, but the
size)
*Sediment - Small pieces of rock
created by mechanical weathering
(mud, sand or silt)
Examples of Mechanical
Weathering
Camel Rock - Santa Fe, NM
Example of Mechanical Weathering
Wind and Water Erosion
© Jon Benignus, 2011
vi. Chemical
Weathering – occurs
when rock is changed
into a new substance
as a result of
interaction between
elements in the air or
water and minerals
(example – iron
rusting)
Why are the rocks
red?
Erosion-movement of
weathered material
ii. Erosion
Occurs when
weathered
material is
moved by the
action of wind,
water, ice and
gravity
Erosion is transporting
sediment
• 2. Water,
wind, and
glaciers
cause
erosion…
http://www.wwnorton.com/college/geo/animations/glacial_advance_retreat.htm
wind erosion
Loess –
windblown silt
and clay
sediment that
produces very
fertile soil
Water Erosion
• Delta – sediment is
deposited in a fanlike landform when
a river enters an
ocean
Glacial Erosion
• Glacier – a large, long-lasting
mass of ice that moves because of
gravity
• Glaciation – changing of landforms
by slowly moving glaciers,
• Moraine – rocks left behind from a
glacier that form a ridge or hill
Glacier
Moraine
V. Distribution of Physical Features
on Earth:
• How do plate
tectonics,
weathering and
erosion affect the
location &
distribution of
physical features?
• a. For the Ring of Fire, the location is
due to being where the crust of the
earth is very thin. This is the primary
factor, plate tectonics, not climate.
• b. For the Great Plains, climate &
type of soil are the primary factors in
the location of this region.
• c. The climate of the Great Plains is
Humid Continental, Semiarid and
Humid Subtropical.
• The type of soil is a major factor,
in the Ring of Fire .Volcanic soil
can be very fertile, as well as the
soil in the Great Plains.
• Tropical Rainforest are located
between the 23 ½ N Tropic of
Cancer & 23 ½ Tropic of
Capricorn, causes these areas to
be quite warm and to have a lot of
rain.