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Physical Geography
How do physical process affect:
planetary ecosystem consisting of the atmosphere, the
geosphere (lithosphere), the hydrosphere, and the
biosphere ECOSPHERE
LITHOSPHERE
http://mediatheek.thinkquest.nl/~ll125/images/struct.jp
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Solid, rocky crust covering entire planet.
• Three main layers
• the core, or the inner layer
• the mantle, in the middle
• the crust.
• 100 kilometers (60 miles) deep in
most places, includes the brittle
upper portion of the mantle and
the crust.
• It is broken into huge sections
called tectonic plates.
• The movement of the
lithosphere, called plate
tectonics, is the reason behind a
lot of Earth's most dramatic
geologic events.
• always moving, but very slowly.
www.space.gc.ca
ATMOSPHERE
• 78% Nitrogen
• Just under 21% Oxygen
• less than 1% argon,
carbon dioxide & other
gasses
•Water vapor and dust
are also part of Earth’s
atmosphere.
•acts as a gigantic filter,
keeping out most
ultraviolet radiation while
letting in the sun’s
warming rays.
The air surrounding Earth HYDROSPHERE All the water in or near the Earth
• The hydrosphere can be liquid, vapor, or ice.
• exists on the surface in oceans, lakes and
rivers.
• exists below ground—as groundwater, in wells
and aquifers.
• Water vapor is most visible as clouds and fog.
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BIOSPHERE
Composed of all living organisms
• Plants
• Animals
• One-celled organisms
• Made up of the parts of Earth where
life exists.
• Since life exists on the ground, in
the air, and in the water, the
biosphere overlaps all of Earth’s
spheres.
• Measures about 20 kilometers (12
miles) from top to bottom
• Almost all life exists between about
500 meters (1,640 feet) below the
ocean’s surface to about 6
kilometers (3.75 miles) above sea
level.
•7 continents – Africa, Asia, Antarctica, South America,
North America, Europe & Australia
•5 Oceans – Southern, Arctic, Pacific, Indian, Atlantic
Continental Drift
The theory that the land of the earth was once connected as one
large super continent (Pangaea) and has moved “drifted” to its
current locations (still moving)
Plate Tectonics
The theory that the crust of the earth is broken up into plates (8
major and many minor) that “float” on the mantle The plate boundaries of the world.
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Subduction
When a sea plate and continental plate collide, the heavier sea plate
DIVES under the lighter continental plate. The sea plate then is
heated and becomes magma which escapes through volcanoes.
Spreading
When sea plates pull apart leaving a rift, or deep crack.
Magma wells up between the two plates to make
underwater volcanoes and ridges.
Volcano
mountain
formed by
lava (magma)
that breaks
through the
earth’s crust.
Ring of Fire
area along the edge of the Pacific Ocean that is a zone
of frequent earthquakes and volcanoes.
Folding
when moving plates squeeze the earth’s surface until it
bends the layers of rock.
Faulting
When moving plates
grind past each other,
creating cracks in the
curst.
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Earthquake
sudden, violent moving of plates along a fault where
built up pressure suddenly snaps and shifts.
Water erosion
fast-moving water cuts into
the land as it flows
downstream. Ocean waves
can also erode coastal cliffs.
WATER is the most
significant cause of erosion.
Water Erosion creates
canyons
Delta
the flat, low-lying plain that
sometimes forms at the
mouth of a river from
deposits of sediments.
Deltas form as rivers
empty their water and
sediment into another
body of water, such as an
ocean, lake, or another
river.
They are called deltas
because the alluvial
deposit at the river’s
mouth looks like the Greek
letter delta (∆)