MINERAL RESOURCE ESTIMATES AND PUBLIC POLICY 



11 



amount of natural gas actually on hand; it also 

 wants to know the extent of potential resources and 

 the effect of price on their exploration and develop- 

 ment. At the regional or local level, decisions with 

 respect to the designation of wilderness areas and 

 parks, the construction of dams, and other matters 

 related to land use involve appraisal of the distri- 

 bution and amount of the resources in the area. 

 The questions of the need for an international 

 regime governing the development of seabed re- 

 sources, the character such arrangement should 

 have, the definition of the area to which it should 

 apply also involve, among other considerations, 

 analysis of the probable character, distribtuion, and 

 magnitude of subsea mineral resources. 



And coming to the forefront is the most serious 

 question of all — namely, whether or not resources 

 are adequate to support the continued existence of 

 the world's population and indeed our own. The pos- 

 sibility to consider here goes much beyond Malthus' 

 gloomy observations concerning the propensity of 

 a population to grow to the limit of its food supply, 

 for both population and level of living have grown 

 as the result of the consumption of nonrenewable 

 resources, and both are already far too high to 

 maintain without industrialized, high-energy, and 

 high mineral-consuming agriculture, transportation, 

 and manufacturing. I will say more about this ques- 

 tion later, but to indicate something of the magni- 

 tude of the problem let me point out that, in attain- 

 ing our high level of living in the United States, we 

 have used more minerals and mineral fuels during 

 the last 30 years than all the people of the world 

 used previously. This enormous consumption will 

 have to be doubled just to meet the needs of the 

 people now living in the United States through the 

 remainder of their lifetimes, to say nothing about 

 the needs of succeeding generations, or the increased 

 consumption that will have to take place in the 

 lesser developed countries if they are to attain a 

 similar level of living. 



CONCEPTS OF RESERVES AND RESOURCES 



The focus of most of industry's concern over the 

 extent of mineral resources is on the magnitude of 

 the supplies that exist now or that can be developed 

 in the near term, and this is of public interest also. 

 Many other policy decisions, however, relate to the 

 much more difficult question of potential supplies, 

 a question that to be answered properly must take 

 account both of the extent of undiscovered deposits 

 as well as deposits that cannot be produced profit- 

 ably now but may become workable in the future. 

 Unfortunately, the need to take account of such 



deposits is often overlooked, and there is a wide- 

 spread tendency to think of potential resources as 

 consisting merely of materials in known deposits 

 producible under present economic and technologic 

 conditions. 



In connection with my own involvement in re- 

 source appraisal, I have been developing over the 

 last several years a system of resource classification 

 and terminology that brings out the classes of re- 

 sources that need to be taken into account in ap- 

 praising future supplies, which I believe helps to 

 put the supply problem into a useful perspective. 

 Before describing it, however, I want to emphasize 

 that the problem of estimating potential resources 

 has several built-in uncertainties that make an accu- 

 rate and complete resource inventory impossible, 

 no matter how comprehensive its scope. 



One such uncertainty results from the nature of 

 the occurrence of mineral deposits, for most of them 

 lie hidden beneath the earth's surface and are diffi- 

 cult to locate and to examine in a way that yields 

 accurate knowledge of their extent and quality. 

 Another source of uncertainty is that the specifica- 

 tions of recoverable materials are constantly chang- 

 ing as the advance of technology permits us to mine 

 or process minerals that were once too low in grade, 

 too inaccessible, or too refractory to recovery profit- 

 ably. Still another results from advances that make 

 it possible to utilize materials not previously visual- 

 ized as usable at all. 



For these reasons the quantity of usable resources 

 is not fixed but changes with progress in science, 

 technology, and exploration and with shifts in eco- 

 nomic conditions. We must expect to revise our 

 estimates periodically to take account of new de- 

 velopments. Even incomplete and provisional esti- 

 mates are better than none at all, and if they 

 differentiate known, undiscovered, and presently 

 uneconomic resources they will help to define the 

 supply problem and provide a basis for policy de- 

 cisions relating to it. 



The need to differentiate the known and the re- 

 coverable from the undiscovered and the uneconomic 

 requires that a resource classification system con- 

 vey two prime elements of information: the degree 

 of certainty about the existence of the materials 

 and the economic feasibility of recovering them. 

 These two elements have been recognized in exist- 

 ing terminology, but only incompletely. Thus as 

 used by both the mining and the petroleum indus- 

 tries, the term reserves generally refers to eco- 

 nomically recoverable material in identified deposits, 

 and the term resources includes in addition deposits 

 not yet discovered as well as identified deposits that 



