Name________________________________________ Period___________

Chapter 19: Section 2: Directed Reading Pages 475-478

Section: Features of the Ocean Floor (page 475) ______ 1. The shallow sea floor between the shoreline and the deep-ocean bottom is

called the

a. continental margin. b. deep-ocean basin. c. continental crust. d. oceanic crust.

______ 2. Continental margins are made up of continental crust

a. and a thin sediment layer. b. and a thick wedge of sediment.

c. without a sedimentary layer. d. or a sedimentary layer.

CONTINENTAL MARGINS (page 475) ______ 3. The part of the continent covered by water is called the

a. shoreline. b. continental margin. c. continental shelf. d. deep-ocean basin.

______ 4. The continental shelf slopes gently from the shoreline, and drops about 0.12 m

every

a. 10 m. b. 100 m. c. 1,000 m. d. 10,000 m.

______ 5. the average depth of the water covering a continental shelf is about

a. 6 m. b. 60 m. c. 160 m. d. 600 m.

______ 6. The continental shelf is part of the

a. continental margin. b. deep-ocean basin. c. ocean surface. d. oceanic crust.

7. V-shaped valleys in the continental shelf and continental slope are called ___________.

8. What is one place submarine canyons are often found?

9. How can turbidity currents help form submarine canyons?

10. How do turbidity currents form?

DEEP-OCEAN BASINS (page 476) 11. What is the name of the deepest place in Earth’s crust?

12. Where is the deepest place in Earth’s crust located?

13. About how deep is the deepest place in Earth’s crust?

14. In the deep-ocean basins, what is a trench?

15. How do trenches form in the deep-ocean basins?

16. About half of the deep-ocean basins are covered by ___________________________.

17. The flattest regions on Earth are __________________________________________.

18. Layers of fine _____________________________________ cover the abyssal plains.

19. How does the age of the oceanic crust affect the thickness of sediments on the abyssal

plains?

20. The most prominent features of ocean basins are _____________________________.

21. Mid-ocean ridges form underwater ________________________________________.

22. What is one place where a mid-ocean ridge rises above sea level?

23. Where do seamounts form?

In the space provided, write the letter of the definition that best matches the term or phrase. _____ 24. guyot a. an area of increased volcanic activity where seamounts form

_____ 25. hot spot b. submerged seamount with a flat top

_____ 26. seamount c. a seamount that rises above the ocean

_____ 27. atoll d. an oceanic island that is in the process of being eroded into a

guyot

_____ 28. oceanic

island

e. submerged volcanic mountain taller than 1 km