CHAPTER 1 

 The Ocean: Its Potentialities and Products 



The area of the surface of the earth is 196,950,277 square miles, of which 

 139,295,000 square miles, or 70.73 per cent, are occupied by ocean (Lambert 

 1926). Its average depth has been estimated to be 2.38 miles, and the greatest 

 depth yet found is 6.7 miles (5900 fathoms). Its volume has been calculated to 

 be about 331,000,000 cubic miles. To the casual observer the ocean is a barren 

 waste chiefly used for transportation. Actu&Uy, it is teeming with both plant and 

 animal Hfe. The largest animals and the tallest plants grow there, and nowhere 

 else can such large quantities of excellent food be obtained with so little effort. 



Potential Resources of the Ocean 



Sea water is "water" only in the sense that water is the dominant substance 

 present. Actually, it is a solution of many salts and gases, not to mention a tre- 

 mendous number of living organisms, most of which are very minute. Through- 

 out the ages there has been a steady movement of materials from the land mto 

 the ocean. The greatest addition is enormous quantities of materials, both m 

 solution and in suspension, which are carried by the water in the rivers. It has 

 been estimated that 71,389 cubic miles of sea water evaporate each year and 

 return to the ocean either in the form of rain or water from the rivers. The latter 

 amounts to about 20,900 cubic miles of water annually which brings 2,735,000,000 

 metric tons of dissolved salts in the ocean (Table 1). In addition, vast quantities 

 of suspended mud and silt are carried by the rivers into the ocean and deposited 

 principally near the mouths of the rivers. 



Other agencies which contribute to the salts in the ocean are volcanoes, sub- 

 marine fissures, fumaroles, springs, glaciers, and even lightning which oxidizes 

 some atmospheric nitrogen to oxides of nitrogen which dissolve in water to form 

 nitric acid, which is then dissolved by rain and eventually reaches the ocean. 



The total quantity of soluble salts in the ocean is very great-about 5 X lO^^ 

 metric tons " (Sverdrup, Johnson, and Fleming 1946), which is enough to form 

 a layer of dried salts about 500 feet deep over the surface of the dry land. 



The composition of sea water has been the subject of many elaborate analytical 

 investigations, which have shown that, although it varies considerably in concen- 

 tration, the composition of the saline matter which it contains is remarkably uni- 

 form. Sea water is mainly a solution of the chlorides and sulfates of sodium, mag- 

 nesium, calcium, and potassium, although it contains appreciable amounts of 

 bromine, iodine, iron, silicon, carbonate, and phosphate. Other elements which 

 have been found in the salts of sea water include aluminum, manganese, phos- 

 phorus, strontium, barium, rhubidium, fluorine, copper, nickel, vanadium, lithium, 

 ** Clarke (1924) estimated the amount to be 46.188 X 10^^ metric tons (Table 1). 



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