28 



Regardless of the number of elements and compounds present in sea 

 water, their extraction depends on a technolosry that would make the 

 effort economically profitable. At the present level of technoloj^ical ca- 

 pability, and takinsr into consideration such factors as ooerating costs 

 and cheaper, competitive sources, distribution costs, and consumption 

 rate, it ]ias been shown that only six minerals can be profitably ex- 

 tracted. These .are : salt, magnesium, sulphur, potassium, bromine, and 

 boron. Any mineral with concentration below that of boron is con- 

 sidered economically unprofitable to extract.*^ 



IV, Technology and Economics 



The discussions thus far have dealt with "deposits" on, in, and 

 under the ocean floor. Under the proper circumstances such deposits 

 are converted by man into "ore bodies". To a geoloarist, an ore is de-fined 

 as a deposit that can he mined at a fro-fit. In order to accomplish this 

 conversion, a venture requires the quantitative presence of a deposit in 

 a certain environment, and the technology to extract the mineral, 

 process it, and market it for a profit. 



A close relationship thus exists between technology and economics, 

 in which the recovery of resources is a business venture primarily 

 economic and only secondarily technologic. The economic factors, how- 

 ever, interact in a complex manner sometimes reflecting the immediate 

 impact of technolo<rical development. 



In the case of the ocean resources, mining of hard mineral deposits 

 depends mainly on economics. The extraction of subsurface deposits, 

 chiefly petroleum, is in a closed sequence in which economic demands 

 spur technology and technology subsequently pushes the market to 

 demand further technology. This section examines the economics and 

 technology for the extraction of hard minerals, oil, and gas. The most 

 significant of the hard minerals are the phosphorites and the man- 

 ganese nodules, both of which will need to be harvested by mining 

 techniques. Oil and gas resources are extracted through holes drilled 

 in the seabed — a technique already in practice, within water-depth 

 limitations. 



Harvesting Hard Minerals from the Seabed 



Mining hard mineral deposits from the sea floor resembles more 

 closely the harvesting of fish than mining as practiced on land. The 

 equipment used for undersea mining operations is simple and un- 

 sophisticated, adapted for the most part from similar land mining 

 equipment. Table V shows the types of mining techniques and the time- 

 table projections for the year 2000 to a depth of 1,000 feet.^^ For the 

 immediate future, however, the most promising of these techniques is 

 essentially the principle of dredging. Some of the dredges have the 

 capability to dig and scoop consolidated sediments. Other types employ 

 hydraulic pumping and air lifting actions, strictly for surface uncon- 

 solidated sediments. 



♦''W. F. Mcllhenny and D. A. Ballard. "The sea as a source of dissolved chemicals." /n 

 "Symposia on Economic Importance of Chemicals from the Sea." (Washington, Division 

 of Chemical Marketing Economics, American Chemical Socle tv. 1963). 



« Gor-'on O. Pherson. "Mining industry's role in develonment of undersea miniuc." 7w 

 "Exploiting the Oeean." Transactions of the 2d Annual Marine Technology Conference 

 and Exhibit, June 27-29, 1966. (1966), page 195. 



