2. 2/3 of Earth’s surface  covered by ocean Exist on Earth for more than 3 billion yrs. 5 major oceans: Pacific, Atlantic, Indian, Southern, Artic Control Earth’s temperature Create weather patterns Water source - Support all life form

3. Ocean Basins =low points on the Earth’s surface Water flows into basin =create ocean Hundreds of millions of years for oceans to fill up to present levels from water that ran off the continents

4. Planet first formed  hot ball of molten rock Outside of Earth cooled down Heat released from deep within the planet through volcanoes Water inside volcanic materials also released into the atmosphere  form of water vapour Water vapour cooled & condensed = fall on to Earth’s surface as rain Gravity causes water to fall downhill  water that fell collected in the lowest parts of Earth’s surface- the ocean basins Original water on planet came from ice in comets that hit the young Earth

5. Has interesting & varied landscape like Earth’s continents Features found on land: mountain ranges, valleys, flat plains, canyons, and volcanoes  also exist on ocean floor 2 distinct parts -Largest: middle part (general ocean basin) -Rising outside edges (continental margins)

6. Tectonic plates =large sections of rock that the entire surface of Earth is made up of Sections of rock are solid but float over a layer of molten rock (magma) Magma heats up =molten rock rises Pressure =force 2 plates apart 2 types of tectonic plates -Continental: lie under continents -Oceanic plate: lie under oceans, dense

7. Plates pushed apart  magma oozes up into the empty space Under ocean =mid-ocean ridge Magma cools at mid-ocean ridges  becomes newest rock on planet Rising & hardening of magma forces plates to continually move apart  ocean floors grow wider & wider Plates moving apart from mid-ocean ridge must come in contact with other plates.

8. Subduction =process where oceanic plate collides with continental plate  the denser oceanic plate forced to slip underneath continental plate When subduction occurs  ocean trench is formed Trench =long V-shaped groove that marks boundary between oceanic plate & continental plate Ridges =develop usually in middle of ocean basin Trenches = tend to develop near outer edges Trench

9. Abyssal plains =wide, flat areas that are stretching between areas of trenches & mid-ocean ridges Make up 30% of Atlantic ocean floor & more than 75% of Pacific ocean floor These flat areas  broken by occasional underwater peak called a seamount Seamount = an old inactive volcano that once developed near a mid-ocean ridge

10. Continental margins = regions of the ocean floor that lie underwater along the edge of the continents These margins are made up of: - continental shelf =flat area that extends from continent’s shoreline to ocean basin - continental slope =steep area that drops off rapidly to the ocean basin from edge of the continental shelf During last ice age  continental shelves in northern hemisphere =not under water More ocean water became locked up as ice  water level fell leaving the shelves exposed

11. Sediments  carried into the ocean by rivers flowing off the continents Sediments build up along the steep continental slope Build-up becomes too big =gravity suddenly causes slope to give way Resulting collapse =turbidity current Turbidity current =underwater landslide that can travel hundreds of km down the continental slope & out along ocean floor Turbidity currents  deposit piles of sediment that form the continental rise Continental rise =between continental slope & abyssal plain.

12. Some turbidity currents  powerful enough to carve out large sections of continental shelf & continental slope =creates submarine canyons Result =underwater landscape Submarine canyons  also found in regions where large rivers reach ocean

13. http://www.google.ca/imgres?imgurl=http://1.bp.blogspot.com/_YAvmwh92iy8/S8LqdeZXSoI/AAAAAAAAH0U/Q6LCkKb0g30/s1600/dolph in_7.jpg&imgrefurl=http://princessbbyin.blogspot.com/2010/04/i-love-world-i-love-sloggi- too.html&usg=__1s9ekeJFw4OnCvVUbdYjy89JT3k=&h=1024&w=1280&sz=376&hl=en&start=0&zoom=1&tbnid=NkeaU5Evf_1DxM:&tbnh=135& tbnw=178&ei=b8juTbucJqjOiAL8qZHrAQ&prev=/search%3Fq%3Docean%2Bdolphin%26um%3D1%26hl%3Den%26rls%3Dcom.microsoft:en- ca:IE- SearchBox%26rlz%3D1I7ACGW_enCA397CA397%26biw%3D1345%26bih%3D612%26tbs%3Disz:l%26tbm%3Disch&um=1&itbs=1&iact=hc&vp x=325&vpy=261&dur=368&hovh=201&hovw=251&tx=140&ty=130&page=1&ndsp=18&ved=1t:429,r:7,s:0&biw=1345&bih=612 http://www.layoutsparks.com/1/164546/water-wave-natural-sea.html http://www.google.ca/imgres?imgurl=http://www.volcano-facts.com/volcano-wallpapers/volcano-wallpaper- 1.jpg&imgrefurl=http://www.volcano-facts.com/volcano-wallpapers.php&usg=__2UPagG1rmY- vW4PYdRXzQ1mXmUY=&h=768&w=1024&sz=120&hl=en&start=0&zoom=1&tbnid=mII0Twudd33RLM:&tbnh=125&tbnw=165&ei=R9zuTfnrB_ LZiALyh5nrAQ&prev=/search%3Fq%3Dvolcano%26um%3D1%26hl%3Den%26sa%3DX%26rls%3Dcom.microsoft:en-ca:IE- SearchBox%26rlz%3D1I7ACGW_enCA397CA397%26biw%3D1345%26bih%3D612%26tbs%3Disz:l%26tbm%3Disch&um=1&itbs=1&iact=hc&vp x=226&vpy=149&dur=179&hovh=194&hovw=259&tx=102&ty=89&page=1&ndsp=21&ved=1t:429,r:1,s:0&biw=1345&bih=612 http://www.google.ca/imgres?imgurl=http://www.dicomtech.com/wp-content/uploads/2011/05/live-satellite-images-of- earth.jpg&imgrefurl=http://www.dicomtech.com/satellite-tv/is-it-possible-to-see-live-satellite-images-of-earth/attachment/live-satellite- images-of- earth/&usg=___YXdp9daIjXNaIeh6HgDn46AI7E=&h=512&w=512&sz=138&hl=en&start=0&zoom=1&tbnid=5oqA5lsitfCJvM:&tbnh=135&tbnw=1 34&ei=A_3uTfqyAYndiALt4JjrAQ&prev=/search%3Fq%3Dsatellite%2Bearth%26um%3D1%26hl%3Den%26rls%3Dcom.microsoft:en-ca:IE- SearchBox%26rlz%3D1I7ACGW_enCA397CA397%26biw%3D1345%26bih%3D612%26tbm%3Disch&um=1&itbs=1&iact=rc&dur=106&page=1&n dsp=21&ved=1t:429,r:0,s:0&tx=93&ty=68 http://www.google.ca/imgres?imgurl=http://www.deviantart.com/download/48968171/Underwater_Ocean_Floor_Light_by_Della_Stock.jpg &imgrefurl=http://www.deviantart.com/deviation/48968171/&h=2436&w=3604&sz=7244&tbnid=ITMVOF_aUiM48M:&tbnh=101&tbnw=150& prev=/search%3Fq%3Docean%2Bfloor%26tbm%3Disch%26tbo%3Du&zoom=1&q=ocean+floor&usg=__yjXlGQPkSzlKqsGL-EDHsWP- Wzs=&sa=X&ei=O_3uTePcK4TOiALM8qH1AQ&ved=0CC8Q9QEwAg http://www.google.ca/imgres?imgurl=http://static.panoramio.com/photos/original/5583273.jpg&imgrefurl=http://www.panoramio.com/pho to/5583273&usg=__- Fb7UbKvloPMGkwIhqWVHKvm1p4=&h=2304&w=3072&sz=2948&hl=en&start=0&zoom=1&tbnid=OwWQR8sHG8R6gM:&tbnh=122&tbnw=1 44&ei=mgbvTYjiAbTdiAL5yZDrAQ&prev=/search%3Fq%3Dpacific%2Bocean%26um%3D1%26hl%3Den%26rls%3Dcom.microsoft:en-ca:IE- SearchBox%26rlz%3D1I7ACGW_enCA397CA397%26biw%3D1345%26bih%3D612%26tbs%3Disz:l%26tbm%3Disch&um=1&itbs=1&iact=hc&vp x=284&vpy=307&dur=968&hovh=194&hovw=259&tx=153&ty=179&page=1&ndsp=21&ved=1t:429,r:15,s:0&biw=1345&bih=612 BC science 8 textbook