Earth’s Oceans
Chapter 6
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6
Video:
http://www.youtube.com/watch?v=3GRA7ilM708
Creatures of the deep!!
Tiny single
celled plants
Large
mammoth
whales
Why important to you
 Source of food
 Indirect source of fresh water
71% of Earth’s surface
97% salt
One continuous body of water
WHAT WE KNOW

5 major oceans
Sea- part of an ocean surrounded
by land
Pacific
-Largest
-deepest
O
c
e
a
n
s
Atlantic
-2nd largest
Major
Player in
the water
cycle

Salt is not evaporated with water
Dissolved
mixture of
solid &
gases
Most Common Salt
Sodium chloride
(table salt)
Properties of
Ocean H2O
Salinityamount of
dissolved
salt
96% pure
water
Ocean
Volcanoes
-lava, rocks
Erosion
of Land
Why does the amount of salt vary
from place to place?
a. low where fresh water meets
ocean water (diluting)
b. high in polar and tropical
regions where evaporation takes
place
c. Animal life (shells)
Waves
Where do salts
come from?
02
CO2
Plants &
photosynthesis
Byproduct
Gases
1. Anywhere there is vegetation
2. Cold Water holds more gases then warm
3. Cold water carries O2 to lower regions of
the ocean
Most direct sunlight
Water mixed by currents and waves
Temp. remains constant
Temp drops lots!
Cold/warm water do not mix well together due to
density
Temp varies with seasons and current
Abyssal Zone
extremely cold (just above freezing)
3 Ocean Zone are not found in polar regions
Ocean Wonders
Topography
 Higher mountains, deeper canyons, &
larger and flatter plains
 More volcanic activity
 More severe earthquakes
 Thinner crust
Ocean Floor
Shoreline does not mark the edge of the continent
-marks the average position of sea level
Shelf
Slope
Continental Margin- underwater edge of
continent meets ocean crust
Continental Shelf Continental Slope
Gentle sloping sediment deposits
best fishing
lg. deposits of minerals (oil &
gas)
Boundary between
continental crust and ocean
floor
Continental Rise
- large sediment deposits from
the slope
- turbidity currents
-submarine canyons
Ocean Floor
Abyssal PlainLarge flat areas of
the ocean floor
Formation -great
rivers deposit their
sediment into the
ocean
- no deep cracks
(cracks trap
sediment)

a.k.a. ocean basin
Seamounts and
Guyots
Seamounts=
underwater mountains
(formed from
volcanoes)
ex. Hawaii
Guyots- flattened tops
of seamounts
Reefs
Limestone rocks
surrounding tropical
islands
Coral reefslimestone deposits
that contain shells of
animals
Ocean Floor
Mid Ocean Ridge
Trenches
-ocean mountain
ranges
Deepest part of
ocean
-form when molten
liquid flows to the
surface and piles atop
each other
Formed along the
edges of the ocean
-rift valleys (location
for new ocean floor)
Ex. Mariana Trench
OCEAN LIFE

Influenced by:


Sunlight
Water pressure
3 major groups
-plankton
-nekton
-benthos
Largest form
of ocean life
Found near
surface
Animal/plant
like organisms
Tiny
Drift with
currents
Plankton
Ocean life that
swim
Nekton
Found at all
levels of the
ocean
Whales,
dolphins,
fish,
octopues
Benthos
-Live on the ocean floor
-could be near the shore
or deep ocean
Intertidal Zone
Coastal zone lies between the low tide and high tide
zone
Changes daily from land to ocean (temp. changes
constantly)
Few organisms can survive here




Extends from the low tide
zone to the continental shelf
Rich in life, due to lots of
sunlight
Great fishing area
Seafood comes from here!
Neritic Zone
Bathyal Zone
Abyssal Zone
-extends
--covers large flat plains of the
from the
continental slope to the
open ocean
-nekton life (octopus,
whales, fish
-little sunlight
ocean
-very little sunlight able to
penetrate
-dark
-creatures of the deep
- Extreme pressure
Open-Ocean Zones
sonar
seismographic
surveys
Indirect
methods of
ocean floor
testing
radar
Pg. 230
ocean floor
instruments
Echo
sounding
Mapping the Ocean Floor

Waves- pulses of energy that move through
the ocean

as a wave passes, the water moves up and
down
Earthquakes
#1 Wind
Earth’s
gravitational
Pull
WAVES

Only energy moves through the
water….particles of water do
not
move themselves

Energy is passed forward
http://www.forgefx.com/casestudies/prenticehall/ph/waves/waves.htm
Wave Terms
 Crest- highest point of a wave

Trough- lowest point of a wave

Wavelength- the horizontal distance
between a crest and a trough
surf
Undertow

Currents- the movement of large amounts of
water through the ocean



like a river in the ocean,
surface currents caused primarily by wind,
deep currents caused primarily by differences
in density
Tides The rise and fall of ocan water
due to the gravitational pull
of the moon
Two high tides and low tides
every 24 hours and 50
minutes

http://forces.si.edu/arctic/02_02_03.html
http://www.windows2universe.org/earth/Water/ocean_motion.html
http://coralreefsystems.org/
coral reef video