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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 (∆)