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Handout 19-2. Features of the Ocean Floor . 1. The shallow sea floor between the shoreline and the deep-ocean bottom is called the. a . continental margin. . 2. Continental margins are made up of continental crust. b. and a thick wedge of sediment.
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Handout 19-2 Features of the Ocean Floor
1. The shallow sea floor between the shoreline and the deep-ocean bottom is called the • a. continental margin.
2. Continental margins are made up of continental crust • b. and a thick wedge of sediment.
3. The part of the continent covered by water is called the • c. continental shelf.
4. The continental shelf slopes gently from the shoreline, and drops about 0.12 m every • b. 100 m.
5. the average depth of the water covering a continental shelf is about • b. 60 m.
6. The continental shelf is part of the • a. continental margin.
7. V-shaped valleys in the continental shelf and continental slope are called ___________. • submarine canyons
8. What is one place submarine canyons are often found? • Near the mouth of major rivers.
9. How can turbidity currents help form submarine canyons? • Turbidity currents carry sediment down the continental slopes.
10. How do turbidity currents form? • When earthquakes cause underwater landslides • When large sediment loads run down a slope
11. What is the name of the deepest place in Earth’s crust? • The Mariana Trench
12. Where is the deepest place in Earth’s crust located? • The Western Pacific Ocean
13. About how deep is the deepest place in Earth’s crust? • More than 11,000 meters deep • 36,089 ft. • 6.8 miles
14. In the deep-ocean basins, what is a trench? • A long, narrow and steep depression that forms on the oceanfloor.
15. How do trenches form in the deep-ocean basins? • Trenches form in deep ocean basins as a result of subduction of a tectonic plate.
16. About half of the deep-ocean basins are covered by __________. • Abyssal plains
17. The flattest regions on Earth are ____________ • Abyssal plains
18. Layers of fine _________ cover the abyssal plains. • sediment
19. How does the age of the oceanic crust affect the thickness of sediments on the abyssal plains? • Older crust is generally covered with thicker sediments than younger.
20. The most prominent features of ocean basins are _________. • mid-ocean ridges.
21. Mid-ocean ridges form underwater ________. • mountain ranges.
22. What is one place where a mid-ocean ridge rises above sea level? • Iceland
23. Where do seamounts form? • Near hotspots • Areas of increased volcanic activity
a. an area of increased volcanic activity where seamounts form b. submerged seamount with a flat top c. a seamount that rises above the ocean d. an oceanic island that is in the process of being eroded into a guyot e. submerged volcanic mountain taller than 1 km 24. guyot 25. hot spot 26. seamount 27. atoll 28. oceanic island