Homework
• Crossword Puzzle
Learning Targets
•  I can describe the features of the ocean floor
•  I can compare and contrast active and passive continental
margins
Agenda
•  Warm Up
•  Collect/review web quest
•  Ocean floor features
Warm Up: Earth’s Oceans Review
1. The nickname for Earth is “Blue Planet”. Why?
2. How did the oceans form? 3. What added water to the oceans? Warm Up: Earth’s Oceans Review Answers
1. 71% of the Earth’s surface is covered in water
2. Rain condensed from steam from volcanoes
when the Earth cooled
3. Comets hiUing Earth
Ocean Floor Features – label diagram in ISN
Rift Valley
Ocean Floor Features – label diagram in ISN
Rift Valley
Continental Shelf
• Gradually sloping end of a continent that goes
under the ocean. (the beach!)
Continental Slope
• Extends from the outer edge of the continental
shelf down to the ocean floor.
Abyssal Plains
• Flat seafloor area
• Found when oceanic plate is sliding beneath (subducting)
under the continental plate
• Located primarily around the Pacific Ocean (convergent
plate boundaries)
• Much thinner continental shelf; Continental slope
descends abruptly into a deep-ocean trench
• Some subduction zones have liUle or no accumulation of
sediments •  Deepest parts of ocean •  Found near Active Margins
(subduction zones)
•  Most are located in the Pacific
Ocean •  Long, relatively narrow features •  Associated with volcanic activity —
—
Volcanic islands arcs Continental volcanic arcs Continental
shelf
Continental
slope
Trench
Continental
Crust
Abyssal plain
Oceanic
Crust
v Passive continental margins • Found along most coastal areas that
surround the Atlantic Ocean
• Not associated with plate boundaries
•  Experience liUle volcanism and •  Few earthquakes Continent
Continental
shelf
Continental
slope
Continental rise
Continental
Crust
(piled up sediment)
Abyssal plain
Oceanic Crust
Active Continental Margin
•  Active margins are found on coastlines where plates are colliding
(Convergent Boundaries) Passive Continental Margins
•  Found along coastlines where there are no plates colliding (no plate boundary)
Active Margins
Continental
Passive Margins
Shelf
Slope
Rise
Trench
Land Features
Fun Fact:
- Deepest part of the ocean…
-  Mariana Trench (Challenger Deep)