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wCONTENTS
1. Introduction: Mineral resources and mineral resource analysis 1
1.1. Perspective on mineral resources 1
1.2. A conceptual framework for resources and resource analysis 2
1.2.1. Definitions of resource terms and identification of useful concepts 2
1.2.2. The appraisal of resource adequacy, a means for examining resource relations and issues 5
1.3. An overview of resource models and estimation procedures
1.3.1. Classification of resource models 6
1.3.2. Economic resource models 7
1.3.3. Quantity-quality models 7
1.3.4. Geological resource models 8
1.3.5. Geostatistical models 9
1.3.6. Compound models 9
1.4. A brief description of two compound resource models
1.4.1. Perspective 10
1.4.2. The mineral endowment of the Canadian North-west 10
1.4.3. Infrastructure and base and precious metal resources of Sonora, Mexico 12
1.5. A summary of resource definitions and concepts 13
1.6. Appendix: A formal statement of definitions and some concepts 14
2. Resource appraisal by models of economic activities 18
2.1. Overview 18
2.2. Supply and demand|econometric models 18
2.3. Simple life-cycle (time series trend) models 21
2.3.1. Concepts and modelling issues 21
2.3.2. Hubbert's analysis of domestic crude oil resources 24
2.3.3. Other life-cycle studies and comments on application 26
2.4. A life-cycle model with price and technology 31
2.5. Discovery-rate models and oil resources (Hubbert) 32
2.5.1. Overview 32
2.5.2. Theory and data conformability 33
2.5.3. Estimation of parameters 34
2.5.4. Calculation of the relative yield factor, R: the ratio of the yield of undrilled, favourable sediments to the yield of sediments already derilled 38
2.5.5. Conceptual issues with respect to (ds/dh) and its use 39
2.5.6. Conclusions 42
2.6. Economic issues of Lieberman's discovery-rate analysis of uranium 43
2.6.1. A general description 43
2.6.2. Some economic issues 43
2.6.3. Two approaches to analysis 45
2.6.4. Productivity and inflation effects on discovery rates 46
2.6.5. An approximate adjustment of Lieberman's analysis for inflation effects 47
2.6.6. What adjustment for future reserve additions? 48
2.6.7. The ratio 49
2.6.8. Summary 50
2.7. A discovery-process model and the estimation of future oil and gas supply 52
2.7.1. Perspective 52
2.7.2. The discovery-process model 52
2.7.3. Predicted discoveries 53
2.7.4. The estimation of potential supply 53
2.8. Appendices 54
2.8.1. Derivation of equation for first-derivative logistic with price and technology variables 54
2.8.2. Demonstration of the effects of mixing drilling yields from two regions 55
3. Quantity-quality relations (models) 59
3.1. Perspective 59
3.2. Lasky's initial treatise: a benchmark 59
3.3. Lasky on the appraisal of metal resources 62
3.4. Musgrove's exposition of exponential relations 62
3.5. Uraniu and resources: a departure from exponential relationsm reserve 64
3.6. Cargill, Root, and Bailey's use of production data 65
3.7. Singer and DeYoung|A Lasky relation across deposits 68
3.8. Model structure 69
3.8.1. The influence of support 69
3.8.2. The influence of correlation 71
3.8.3. The need for a more general approach to model structure 72
3.9. Issues in the use of quantity-quality relations for prediction 75
3.9.1. Perspective 75
3.9.2. Selection of the function to be fitted to tonnage-grade data 75
3.9.3. Determining the limit to extrapolation 76
3.9.4. Estimation of endowment or resources of a region 79
4. Deterministic geological methods 93
4.1. Introduction 93
4.2. Crustal abundance 93
4.3. The abundance-reserve relationship 94
4.4. Estimation by analogy 95
4.4.1. Perspective 95
4.4.2. Simple density 96
4.4.3. Compound density 96
4.4.4. Some examples of the methodology and criticisms 97
4.5. World uranium resource estimates 106
4.5.1. Perspective 106
4.5.2. Estimation 106
4.5.3. Summary of total resource estimate 111
4.5.4. An international assessment by experts 112
4.5.5. Some criticisms and speculations 112
4.6. Composite deterministic models 114
5. Geostatistical models of metal endowment|a conceptual framework 118
5.1. The evolution of geostatistical models 118
5.2. Conditions for a probabilistic model for metal endowment 118
5.3. Geostatistical theory of metal endowment 119
5.4. Taxonomy of models 121
5.5. Geostatistical deposit models 121
5.5.1. The basic model 121
5.5.2. Metal density 122
5.5.3. Multivariate models 122
5.5.4. Spatial models 122
5.5.5. Trend models 123
5.5.6. Composite multivariate and trend models 123
5.6. The crustal-abundance (element distribution) model 123
5.6.1. Concepts and theory 123
5.6.2. The case for the lognormal distribution 126
5.7. Simplified summary of concepts 128
5.8. Appendix: Derivation of the probability density for metal m from the densities for n, t, and q 129

6. A multivariate model for wealth (a value aggregate of metals) 132
6.1. Perspective and theory 132
6.2. The Harris model 133
6.2.1. The basic proposition 133
6.2.2. The geological model 133
6.2.3. Usable variables 134
6.2.4. The value measure 135
6.2.5. Incomplete geological information 137
6.2.6. The use of the expanded information 139
6.2.7. Relating probability, mineral wealth, and geology 140
6.2.8. Multiple discriminant and Bayesian probability analysis 144
6.2.9. A word on discriminant analysis 146
6.2.10. The analysis 147
6.2.11. Test of the model on Utah 151
6.3 A model of the conditional expectation for mineral wealth 152
6.3.1. Theory 152
6.3.2. The mineral-wealth equation for Terrace, British Columbia 153
6.4. A probabilistic appraisal of the mineral wealth of a portion of the Grenville Province of the Canadian Shield 154
6.4.1. Procedure 154
6.4.2. Probability analysis 155
6.5. The models of Agterberg 155
6.6. Some issues about mineral-wealth models 156
6.7. Appendix 158
6.7.1. Derivation of the aggregate mineral-wealth probability distribution 158
6.7.2. Siscriminant analysis 158
7. Occurrence models 164
7.1. Perspective on occurrence models 164
7.2. Spatial models 164
7.2.1. Concepts of fitting of function 164
7.2.2. Allais's study 165
7.2.3. Fitting the Poisson 166
7.2.4. Implications of the Poisson 167
7.2.5. Distributions for mines 168
7.2.6. Slichter's work 168
7.2.7. Clustering and the negative binomial 173
7.2.8. Issues regarding spatial models 174
7.3. Multivariate models 177
7.3.1. Theory 177
7.3.2. A number equation 177
7.3.3. A probability model for number of copper deposits for the Abitibi Area, Ontario and Quebec 178
7.4. A compound probability model for number of deposits 181
7.4.1. Theory 181
7.4.2. Application possibilities 182
8. The crustal abundance geostatistical (CAG) approach of Brinck 184
8.1. Relationship to geostatistical theory 184
8.2. The geostatistical relations of DeWijs|a foundation 184
8.3. The extensions made by Brinck 189
8.3.1. Perspective 189
8.3.2. Basis for a probabilistic model 190
8.3.3. Use of the normal probability law for estimation of tonnages 191
8.4. Estimation of average grade 194
8.5. Example of calculations of tonnage and average grades using the lognormal distribution 195
8.6. Importance of block (deposit) size 196
8.7. The variance-volume relationship of DeWijs 199
8.8. The Matheron-DeWijs formula for differing shapes of environment and deposit 200
8.8.1. Perspective 200
8.8.2. The variogram 200
8.8.3. The DeWijsian variogram 203
8.9. Application|an exercise in statistical inference 205
8.9.1. Procedure recapitulated 205
8.9.2. Demonstration on Oslo 205
8.9.3. The case of no usable geochemical data 206
8.10. A comparison of methods|New Mexico uranium 208
8.11. The logbinomial model 209
8.12. Issues of the CAG approach of Brinck 209
8.12.1. Continuity of grade distribution 209
8.12.2. Tonnage-grade relations and Brinck's calculations 210
8.12.3. Estimation of parameters from production and reserve data 210
8.12.4. Crustal abundance and geology 214
8.13. The economic model 215
8.13.1. Overview and recapitulation 215
8.13.2. The cost model 216
8.13.3. Comment on the exploration model 218
8.13.4. Long-term metal price 218
8.14. Brinck's analysis of resources and potential supply 219
9. Univariate lognormal crustal abundance geostatistical models of mineral endowment 224
9.1. Perspective and scope 224
9.2. The analysis by Agterberg and Divi of the mineral endowment of the Canadian Appalachian Region 224
9.2.1. General description of approach 224
9.2.2. Specific relations 224
9.2.3. Estimates 224
9.3. US uranium endowment 226
9.3.1. Estimates by the approach of Agterberg and Divi 226
9.3.2. Estimation of an asymptotic ƒÐ, a modification of the approach of Agterberg and Divi 228
9.3.3. A comparison of estimates 229
9.4. An important qualification 230
9.5. Endowment is not resources or potential supply 231
10. The bivariate lognormal deposit model of PAU|a crustal abundance geostatistical model 233
10.1. General perspective 233
10.2. Demonstration of concepts 234
10.2.1. A simpler model 234
10.2.2. Mathematical expectation 234
10.2.3. Truncation by a cost surface and expectations 235
10.2.4. The solution for ƒ¿ and ƒÀ 236
10.2.5. A numerical example using the simplified hypothetical model 236
10.3. The PAU model 237
10.3.1 The mathematical form 237
10.3.2. Demonstration by PAU on US uranium 238
10.3.3. PAU's African model 240
10.4. The assumption of independence of grade and tonnage in crustal-abundance models 242
10.5. Appendix A: The mathematics of a solution for ƒ¿ and ƒÀ 242
10.5.1. The problem 242
10.5.2. Evaluating the denominator D1 of (10.39) 242
10.5.3. Evaluating the numerator N1 of (10.39) 242
10.5.4. Putting the parts together for E[X1]* 243
10.5.5. Evaluating the denominator D2 of (10.40) 243
10.5.6. Evaluating the numerator N2 of (10.40) 244
10.5.7. Putting the parts together for E[X2]* 245
10.6. Appendix B: Computer program 245

11. The statistical relationship of deposit size to grade|a grade-tonnage relationship 253
11.1. Perspective 253
11.2. Why the concern about this issue? 253
11.3. Perceptions and beliefs 254
11.4. Empirical studies 254
11.5. Difficulties in the statistical analysis of ore-deposit data 256
11.5.1. Contamination of statistical data by economics 256
11.5.2. Truncation 258
11.5.3. Translation 258
11.5.4. Possible remedies 259
11.6. Grade-tonnage relations and crustal abundance 259
11.6.1. Perspective 259
11.6.2. Singer and DeYoung's analysis 260
11.6.3. The PAU model 262
11.7. Final comment 263
12. Size and grade dependency and an explicit treatment of economic truncation: theory, method of analtsis, demonstration, and a case study (New Mwxico uranium) 265
12.1. Overview 265
12.2. Two hypotheses 265
12.3. Theory and model form 265
12.3.1. Theory 265
12.3.2. Specification of the model 266
12.4. A compromise of theory to facilitate estimation 267
12.5. Estimation methods 268
12.5.1. Perspective 268
12.5.2. Cohen's solution 269
12.5.3. The Newton algorithm applied to Cohen's solution 270
12.5.4. Estimation of the parameters ƒÊy and ƒÐy by computer search 272
12.6. Demonstration on a synthetic truncated normal distribution 273
12.6.1. Pverview 273
12.6.2. Generating synthetic sample data from a model 274
12.6.3. Estimating the parameters of the conditional distributions for (X|Yi) 278
12.6.4. Investigating the dependency relationship 279
12.6.5. Estimating the parameters of the marginal distribution (Y) 280
12.7. Analysis of uranium deposits of New Mexico 281
12.7.1. The data 281
12.7.2. Costs: components, relations, and estimates 282
12.7.3. Parameters of the grade distribution 285
12.7.4. The dependency relationship 288
12.7.5. The parameters of the tonnage distribution 289
12.7.6. The model 290
12.8. Conclusions ans some criticisms 291
12.9. Appendices 293
12.9.1. Deivation of equations for Newton's algorithm for Cohen's solution 293
12.9.2. Differentiation of the integrals I', I'' 295
12.9.3. Computer programs SIGMU and SEARCH 296
13. Resource analyses which used geological analysis and conventional assessments of subjective probabilities for mineral occurrence and discovery: concepts, methods, and case studies 310
13.1. The concept of subjective probability 310
13.2. Scope 310
13.3 Mineral endowment and potential supply of British Columbia and the Yukon Territory 311
13.3.1. Overview 311
13.3,2. The study design for mineral endowment 311
13.3.3. Economic analysis 314
13.4. Northern Sonora, Mexico 320
13.4.1. Estimation of copper endowment 320
13.4.2. The economic analysis of infrastructure development and potential copper supply 326
13.5. Mineral endowment of Manitoba, Canada 330
13.6. Estimation of uranium resources of New Mexico by Delphi procedures 330
13.6.1. Background 330
13.6.2. Survey design 330
13.6.3. Analysis by cell of initial information 333
13.6.4. Modified Delphi reassessment 335
13.6.5. Probability distributions for the State of New Mexico 338
13.7. The oil resource appraisal by the US Geological Survey (Circular 725): description, critique, and comparison with Hubbert 340
13.7.1. The nature of the appraisal 340
13.7.2. Methodology 343
13.7.3. Comments on methodology 347
13.7.4. The supposed unanimity of recent oil resources estimates (Hubbert versus the Survey) 349
13.8. Mineral resources of Alaska 354
13.8.1. Perspective 354
13.8.2. Methodology 354.
13.8.3. An estimate of expected copper in porphyry deposits 358
13.9. Uranium endowment estimates by NURE 359
13.9.1. General commentary on the NURE appraisal 359
13.9.2. Scope of this section 360
13.9.3. Logistics and approach in general 360
13.9.4. The methodology in perspective and in comparison with other subjective probability appraisal methodologies 361
13.9.5. Some details on design of elicitation 363
13.9.6. Critique of endowment estimation, particularly execution of the elicitation 364
13.9.7. Some possible modifications 369
13.9.8. Final comments 371
14. Psychological, psychometric, and other issues and motivations in the perception of and the assessment of subjective probability 314
14.1. Perspective 314
14.2. The concept of bounded intelligence 314
14.3. Heuristics and biases 375
14.4 Doubts about self-ratings of expertise and about Delphi 378
14.4.1. Expertise and self-ratings in other studies 378
14.4.2. A critique of Delphi methods 379
14.5. Purposeful hedging 380
14.6. Implications of psychometric issues to the appraisal of mineral resources 381
14.7. Preferred procedures 383
15. Formalized geological inference and probability estimation 387
15.1. Perspective and scope 387
15.2. Formalized geoscience which supports active analysis of data by the geologist (approach A)|the uranium endowment appraisal system of Harris and Carrigan 388
15.2.1. Overview of appraisal system 388
15.2.2. The geological decision model|formalized geoscience 391
15.2.3. Preparation and calibration of the appraisal system 400
15.2.4. Selected comments on features of the appraisal system 403
15.2.5. An improved method for linking formalized geoscience to mineral endowment 407
15.2.6. An experiment on the effect of subjective probability methodology on estimates of uranium endowment of San Juan Basin, New Mexico 409
15.3. A comment on PROSPECTOR|a second example of approach A 422
15.3.1. Perspective and scope 422
15.3.2. Some specific features 423
15.3.3. A brief comment on the use of PROSPECTOR for regional analysis of uranium favourability 427
15.4. Genetic modelling, characteristic analysis, and decision analysis (approach B)|a methodology developed by the US Geological Survey 430
15.4.1. Perspective 430
15.4.2. Characteristic analysis 430
15.4.3. Genetic modelling for decision analysis 433
15.4.4. Decision analysis|the integration of characteristic analysis and genetic modelling 434
15.4.5. Some comments about this methodology and appraisal of endowment and resources 437
15.5. Selected comments 438
15.6. Appendix A|mathematical basis for characteristic weights 439
Index 443
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