1. This works by calculating the time it takes for sound waves to travel to the ocean floor and reflect back; we use it to measure the depth of the ocean. 1-1

2. SONAR 1-1

3. On average, there are this many grams of salt per 1,000 grams of seawater. 1-2

4. 35 ppt 1-2

5. This is the depth at which the water temperature drops rapidly. 1-3

6. Thermocline 1-3

7. This is at least one factor that would cause salinity to increase. 1-4

8. Freezing or Evaporation 1-4

9. Between pure and salt water (pick one of these as your answer), this type is more stable because it has a lower freezing point and higher boiling point. 1-5

10. Salt water 1-5

11. There are three main classes of ocean floor sediments and these are two of the three. 2-1

12. Terrigenous – comes from rocks and minerals of the continental crust Biogenous – comes from living sources such as shells and skeletons from tiny marine animals Hydrogenous – forms when chemical reactions cause minerals to crystalize from seawater 2-1

13. When the oceanic plate is sliding beneath (subducting under) the continental plate there is this type of continental margin. 2-2

14. Active continental margin 2-2

15. These are triggered by earthquakes or gravity and are large undersea landslides of mud. They can carve out and create submarine canyons. 2-3

16. Turbidity Currents 2-3

17. These form at divergent plate boundaries where magma rises between the plates and cools, forming new sea floor. 2-4

18. Mid-ocean ridges 2-4

19. This is a ring shaped coral reef that develops around a volcanic island. 2-5

20. Coral atoll 2-5

21. Surface currents are ultimately caused by this. 3-1

22. Wind 3-1

23. This current causes the British Isles and Iceland to have warmer climates than they normally have. 3-2

24. Gulf Stream 3-2

25. Occurs along the western coast of continents and equator and it is when cold deep water comes to the surface. 3-3

26. Upwelling 3-3

27. The global circulation of ocean currents that transports heat, nutrients, and gases is often modeled as this. 3-4

28. Global Conveyor Belt 3-4

29. 3-5 This drives deep ocean currents. They are important to marine animals living in the deep ocean as the retain the oxygen absorbed at the surface as well as the temperature and salinity.

30. 3-5 Density Currents

31. 4-1 The periodic rise and fall of the ocean surface due to the gravitational pulls of the moon and sun.

32. 4-1 Tides

33. 4-2 These tides occur twice a month when high tides are especially high and low tides are especially low.

34. 4-2 Spring tides

35. 4-3 Amount of time it takes the daily tides to cycle.

36. 4-3 24 hours and 50 minutes

37. The difference in water level between high tide and low tide. 4-4

38. Tidal range 4-4

39. This refers to when the Earth, moon, and sun are at right angle to one another and high tides and low tides are moderate. 4-5

40. Neap tides 4-5

41. The measure of dissolved salts in water. 5-1

42. Salinity 5-1

43. 5-2 A cone-shaped undersea mountain of volcanic origin that rises high above the ocean floor.

44. 5-2 Seamount

45. A flat-topped seamount. 5-3

46. Guyot 5-3

47. A large flat area on ocean floor, composed of sediments that originated mostly on continents. 5-4

48. Abyssal Plain 5-4

49. A partially enclosed body of water along the coast where freshwater (from rivers/streams) meets and mixes with salt water from the ocean. 5-5

50. Estuary 5-5

51. Why are diatom (phytoplankton) shells found in ocean-floor sediments?

52. They settle to the ocean floor after the diatoms die.