In items 11-48 through 11-51, select from column 

 B the oceanographlc related term or phrase appli- 

 cable to each definition in column A. 



11-48. 



11-49. 



11-50. 



11-51. 



Definitions 



The total amount of 

 dissolved solid mate- 

 rial, expressed in 

 grams, contained in 

 1,000 grams of sea 



B. Terms and 

 Phrases 



1. Reverber- 

 ation 



2. Salinity 



water 



3. 



Shadow 

 zone 



The scattering of 







sound from a source 



4. 



Sound 



back toward the 





velocity 



source 







The rate at which 

 sound energy propa- 

 gates in relation to 

 temperature, pres- 

 sure, and salinity 



The regions in the 

 ocean where sound 

 energy penetration 

 is negligible 



11-52. What does the temperature-salinity (T-S) 

 diagram identify? 



1. Water mass and type only 



2. Water mass and viscosity only 



3. Water type and viscosity only 



4. Water type, water mass, and viscosity 



11-53. Which of the following statements about 

 the continental shelf is INCORRECT? 



1. The shelf extends outward from the 

 coast to a depth of 1,500 fathoms 

 and comprises about 12 percent of 

 the total ocean bottom 



2. The shelf region is a transition 

 zone between fresh water runoff from 

 land and the more saline waters of 

 the sea 



3. Great mixing of waters and generally 

 unstable water conditions are charac- 

 teristic of the shelf region 



4. Currents in the shelf region commonly 

 run parallel to the shoreline 



11-54. What topographic feature covers the 

 largest area of the ocean bottom? 



1. Continental shelf 



2. Continental slope 



3. Ocean basin 



4. Ocean deep 



68 



11-55. Refer to figure 16-1 in your textbook. 

 The area of the ocean bottom classified 

 as deep can be found only in relation to 

 what topographic feature? 



1. Continental shelf 



2. Continental slope 



3. Ocean ridge 



4. Ocean trench 



Learning Objective: Identify temp- 

 erature gradients in relation to 

 depth in the three ocean layers, 

 three ways in which ocean circula- 

 tion and salinity content relate to 

 solar heat, and two reactions of 

 sound under given conditions. 



11-56. Refer to figure 16-2 in your textbook. 

 Which of the following correctly indi- 

 cates the descending order of the thermo- 

 clines as they are ordinarily found in 

 the oceans? 



1. Warm and shallow ■* rapidly decreasing 

 temperature ■* uniformly cold 



2. Warm and deep ■* rapidly decreasing 

 temperature ■*■ uniformly cold 



3. Shallow with rapidly decreasing temp- 

 erature ■> shallow with temperature 

 decrease slowing ■* uniformly cold 



4. Shallow with rapidly decreasing temp- 

 erature ■*■ uniformly cold ■* slowly 

 decreasing temperature 



11-57. Increases in ocean salinity are primarily 

 caused by 



1. conduction 



2. condensation 



3. evaporation 



4. precipitation 



11-58. Which of the following statements pro- 

 vides the best explanation for the fact 

 that the deep water in tropical oceans 

 originates in higher latitudes? 



1. Water beneath the surface in high 

 latitudes becomes less dense as it 

 flows into the tropics and forces 

 the warmer water under the surface 



2. Surface water in the higher lati- 

 tudes, being less dense than tropical 

 waters, expands over the tropical 

 waters and, in turn, is replaced as 

 it is heated 



3. Surface water in the tropical oceans 

 is heated and expands along the sur- 

 face; as it becomes less dense, the 

 denser water from the polar regions 

 flows in under it 



4. Water beneath the surface in tropical 

 oceans Is constantly forced deeper by 

 the increase of surface layer pressure 

 thereby allowing cold polar water to 

 flow in over it 



