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11.1 Ocean Basins
 The surface of the ocean floor is as varied as the land.
 Basins: low points in the oceans
See page 402
(c) McGraw Hill Ryerson 2007
11.1 Ocean Basins
 The five major oceans (from largest to smallest)
 the Pacific
 the Atlantic
 the Indian
 the Southern
 the Arctic
See page 402
(c) McGraw Hill Ryerson 2007
11.1 Ocean Basins
 Oceans are vital to life:
1. they control temperature
2. create weather patterns
3. provide water for water cycles.
See page 402
(c) McGraw Hill Ryerson 2007
The Origin of Ocean Water
 Oceans have filled over hundreds of millions of years.
 Scientists believe the oceans are more than 3 billion
years old.
See page 404
(c) McGraw Hill Ryerson 2007
The Origin of Ocean Water
 Water may have originally been released from
volcanic eruptions, or arrived on Earth via icy comets.
See page 404
(c) McGraw Hill Ryerson 2007
Features of the Ocean Floor
 Ocean Floors Have:
 Mountain ranges
 Valleys flat plains
 Canyons
 Volcanoes
The ocean topography of the Caribbean
See pages 404 - 405
(c) McGraw Hill Ryerson 2007
Features of the Ocean Floor
 Basin: is the large, flat middle part
 Continental Margins are the edges rising up to the
land
The ocean topography of the Caribbean
See pages 404 - 405
(c) McGraw Hill Ryerson 2007
Ocean Basins
 Changes to the ocean basin occur:
 Through the movement of tectonic plates (MOST)
 Some erosion via storms, earthquakes and icebergs.
See pages 406 - 407
(c) McGraw Hill Ryerson 2007
YOUR TURN
 You are going to complete the rest of your notes using
your book 
 This is good practice for grade 9!!!
Ocean Basins
 Mid-ocean ridges occur
where new rock is
forced up, and ocean
floor spreads outward.
 The Mid-Atlantic Ridge is
the largest example on
Earth
 The Juan de Fuca plate
lies
200 km off Vancouver
Island
See pages 406 - 407
(c) McGraw Hill Ryerson 2007
Ocean Basins
 A trench forms when the dense oceanic plates
run into, and slide under, the continental plates.
See pages 406 - 407
(c) McGraw Hill Ryerson 2007
Ocean Basins (continued)
 Abyssal plains are the pieces of
oceanic crust between a
spreading mid-ocean ridge
and the trench it disappears
into.
 These make up 30% of the
Atlantic sea floor, and 65% of the
Pacific seafloor.
 Abyssal plains can be
covered in 1 km of sediments
See page 407
(c) McGraw Hill Ryerson 2007
Ocean Basins (continued)
 Seamounts are old
volcanic mountains
found on abyssal plains.
The Hawaiian Islands
are an example.
See page 407
(c) McGraw Hill Ryerson 2007
Continental Margins
 Continental margins:
 are part of continental plates
 made up of a continental shelf (averaging 80 km
wide) and a continental slope down to the oceanic
plate.
 were above water during the last ice age.
See pages 407 - 409
Take the Section 11.1 Quiz
(c) McGraw Hill Ryerson 2007
Continental Margins
 Turbidity currents are slides on the slopes, and
can create large submarine canyons in the shelf.
See pages 407 - 409
Take the Section 11.1 Quiz
(c) McGraw Hill Ryerson 2007
The Epipelagic Zone
The upper most layer of the ocean.
Enough light for photosynthesis.
 Base of the food chain.
Majority of marine life found here.
1 to 200m.
The Mesopelagic Zone
Some light penetrates this layer.
Insufficient for photosynthesis!
Still plenty of life here.
 Many organisms are bioluminescent.
200 to 1000m.
The Bathypelagic Zone
The ocean is pitch black.
 No light!
Some bioluminescent animals.
Many animals have small eyes or no eyes at all!
1000m to 4000m.
The Abyssopelagic Zone
Extremely cold temperatures and high pressure.
Many species in this zone are transparent and eyeless.
4000m down the ocean floor.
The Hadopelagic Zone
Water in the deep ocean trenches.
The zone is mostly unknown.
Very few species are known to live here, so a low
biodiversity.