270 



leum resources is illustrated by the following tentative and incomplete data : 

 in 1947 petroleum reserves under the United States continental shelf were esti- 

 mated at around 33 billion barrels and annual offshore production was about 

 25 million barrels, in 1965 known reserves were estimated at some 100 billion 

 barrels and annual offshore production had grown to 240 million barrels which, 

 however, was still only about 7.5 per cent of total United States petroleum pro- 

 duction. In other parts of the world similar rises in annual offshore production 

 and in known reserves have been recorded over the past twenty years. To give 

 but one example, the Komsomolslcaya Pravda of 16 August 1967 reported that 

 enormously rich deposits of oil had been found on the arctic continental shelf 

 of the Soviet Union at depths of twenty to twenty-five metres. The article stated : 



"The Tyumen region alone promises by 1980 — that is, in a dozen years — to 

 yield as much oil as was produced in the entire Soviet Union last year (196C)'". 



Exploration of offshore petroleum resources is proceeding at an accelerated 

 pace in nearly all parts of the world with drilling expenditure growing at a 14 

 per cent compound annual rate. 



Even moi'e spectacular progress has been made in the exploration and exploita- 

 tion of offshore natural gas. In 1950 United States offshore natural gas reserves 

 were estimated at 50 trillion cubic feet and in 1965 they were estimated at 

 150 trillion, in the six-year period 1960 to 1965 offshore gas production has more 

 than doubled from 403 billion cubic feet to 977 billion cubic feet. 



Exploration activity is continuing feverishly. We have all heard, for instance, 

 of the enormous discoveries of natural gas under the North Sea. According to 

 the Oil and Gas Journal of 27 February 1967 the Groningen field alone is reputed 

 to contain 40 trillion cubic feet of natural gas, the Shell/Esso 49/26 field another 

 6 trillion, and several other blocks have reserves in the trillions. 



Up to now I have been speaking exclusively of resources known to exist under 

 the shallow waters of the continental shelf. I have tried to make the point that 

 these resources are known to be valuable and that, at least in the case of petro- 

 leum and natural gas, systematic exploitation of presently known offshore re- 

 sources is likely to be suflScient to cover by itself expected growth in demand. 



The continental shelf, as we have defined it, however, constitutes less than 

 10 per cent of the sea-bed and ocean floor of the world. We must now examine 

 whether the vast, mysterious svibmariue areas plunged in perpetual darkness 

 that lie beyond the continental shelf contain valuable known resources and 

 whether such resources may be commercially exploited on a large scale in the 

 near future, and by the near future I mean within the next decade. In this 

 connexion we shall not refer to the possibility of in-solution mining, which, al- 

 though practicable, does not appear likely, but rather to the potential for ou- 

 bottom and sub-bottom mining. 



Nearly a hundred years ago the "Challenger" expedition discovered the exist- 

 ence of phosphorite and manganese dioxide concretions on the ocean floor. The 

 abundance of such concretions — commonly called nodules — was cf)nfirmed ovei- 

 the years by a number of oceanographic expeditions and their chemical com- 

 position was studied. Manganese nodules, in particular, have attracted attention 

 and the extent of deposits and concentration of the nodules in various locations 

 on the ocean floor have been ascertained with good approximation. Manganese 

 nodules are irregularly spherical in shape, like potatoes, ranging from 0.5 to 25 

 cm. in diameter, and are commonly found on the surface of the ocean floor at a 

 depth of between 1.500-6,000 metres. Concentration of the nodules on the ocean 

 floor, their chemical composition and the extent of the deposits vary widely. II 

 would appear that about 20 per cent of the surface of the Pacific Ocean fioor 

 is covei'ed by nodules sometimes in the almost incredible concentration of .50 kg. 

 per square metre: maximum known metal content of the main materials in the 

 nodules has been determined as follows: 57.1 per cent manganese. 39.5 per cent 

 iron. 2.1 per cent cobalt, 2.9 per cent copper, 2.4 per cent nickel and .5 per cent 

 lead. I do not have world tonnage estimates of manganese nodules : tonnage 

 estimates for manganese nodules lying on the surface of Pacific Ocean sediments 

 are quoted by John L. Mero in his book The Mineral JiCKourcva of the f^ra on 

 page 175. They range from estinuites made by Zenkevitch and Skornyakova of 

 0.9X10" tons to estimates of 17X10" tons. On the basis of those estimates Mr. 

 Mero has attempted conservatively to calculate the reserves of metals in the 

 manganese nodules of the Pacific Ocean : the results are astounding. The nodules 

 contain 43 billion tons of aluminum equivalent to reserves for 20.000 years at 

 the 1960 world rale of consumption as compared to known land reserves for 100 

 years; 35S billion tons of manganese equivalent to reserves for 400,000 years as 



