The document summarizes key features of the ocean floor and continental margins. It describes the continental shelf, slope, and rise where sediments are deposited near the continents. It also outlines the abyssal plains, seamounts, guyots, mid-ocean ridges, trenches, and Challenger Deep found in the deepest parts of the ocean floor.

1. 9 th Grade Chapter 4 Lesson 3 Pgs. 97 – 100 For Student Use Only

2. Geography of Seas Continental Margins: Ocean Basins- deep depressions that contain the oceans Continental Shelf- sandy, gently sloping underwater plain Full of life Well-lit bottom In Tropics- support coral reefs

3. Geography of Seas Continental Margins: Shelf Break- sharp drop off at edge of continental shelf Continental Slope- where the sea floor drops away from the continent abruptly Light fades Water cools as cross the thermocline Fish begin to have bioluminescent

4. Geography of Seas Continental Margins: Continental Rise- area of deep sediments that gently slope toward the deep ocean Sediments could have been deposited after the Great Flood Continental Margin: The continental shelf, slope, and rise. Submarine Canyons- canyons that are cut in the ocean floor

5. Geography of Seas Deep Ocean Floor: Abyssal Plain- average depth of 14,760 feet found at the base of the continental rise Seamounts- mountains that raise above the seafloor. Some seamounts become islands Guyots- unusual flat top mountains

6. Geography of Seas Ocean Floor Mid-Oceanic Ridges- underwater mountain chains that are formed from volcanic activity and sea floor spreading Mid-Atlantic Ridge: Runs along the center of the Atlantic ocean Ocean Ridges: usually form along plate boundaries

7. Geography of Seas Deeps: Oceanic deep- Any area that extends 6000 meters Trenches- huge muddy valleys and cut through abysmal plains Challenger Deep- deepest known layer of the ocean found in the Marianas Trench Trieste was the first submarine to discover it