Designing Optimal Strategies for Mineral Exploration

Few knowledgeable people would deny that the field of mineral exploration is facing some difficult times in the foreseeable future. Among the woes, we can cite a worldwide economic uneasiness reflected by sluggish and at times widely fluctuating metal prices, global financial uncertainties, and relentless pressures on costs despite a substantial slowing down of the rate of inflation. Furthermore, management is forced to tum to more sophisticated and expensive technologies and to look farther afield to more remote regions, as the better­ quality and more easily accessible ore deposits have now been revealed. This rather gloomy outlook should persuade explorationists to cast about for a new philosophy with which to guide mineral exploration through the challenging decades ahead. Once already, in the early 1960s, a call for change had been heard (Ref. 30 in Chapter 1), when it became obvious that the prospecting methods of yesteryear, so successful in the past, could not keep up with the rapidly growing demand for minerals of the postwar period. The answer, a massive introduction of sophisticated geophysical and geochemical technologies backed by new geo­ logical models, proved spectacularly successful throughout the 1960s and the 1970s. But for both economic and technological reasons, the brisk pace of the last two decades has considerably slowed down in the early 1980s, as if a new threshold has been reached.

One Optimizing Mineral Exploration.- 1.1. General Statement.- 1.2. The Mitigation of Uncertainty and Risk in Mineral Exploration.- 1.3. Conclusion: Scope of the Book.- References and Selected Readings.- Two Evaluation of the Probability of Detection of Mineral Deposits.- 2.1. The Detection Process.- 2.2. Geometric Considerations Involved in the Detection of Mineral Deposits.- 2.3. The Theory of Geometric Probabilities as a Foundation for the Evaluation of the Probability of Detection of Mineral Deposits.- 2.4. Evaluation of the Probability of Target Detection by Airborne Geophysical Surveys.- 2.5. Evaluation of the Probability of Target Detection by Ground Geophysical Surveys and Drilling Programs.- 2.6. Probability of equential Detection of Ore Deposits.- References and Selected Readings.- Three Cost of Detection.- 3.1. General Statement.- 3.2. Costing and Cost Estimates.- 3.3. Cost Functions.- 3.4. Tabulation of Cost Functions.- References and Selected Readings.- Four Optimizing Ore Detection.- 4.1. General Statement.- 4.2. Basic Theory of Optimization.- 4.3. Methodology of Optimization.- 4.4. Application of Optimization Theory to Ore Detection.- References and Selected Readings.- Five Application of the Optimization Methodology to the Search for Six Types of Ore Deposits in North America.- 5.1. General Statement.- 5.2. Construction of a Database.- 5.3. Data Processing.- 5.4. Computation of Detection Probabilities.- 5.5. Design of Three Strategies for the Detection of Six Types of Ore Deposits in North America.- References and Selected Readings.- Six Designing Optimized Field Programs for the Detection of Porphyry-Cu-Mo Deposits of the North American Cordillera Belt.- 6.1. General Geological Background.- 6.2. Field Detection Methodology.- 6.3. Statistical Modeling of the Geometric Parameters of Porphyry-Cu-Mo Deposits and their Associated Pyritic Halos.- 6.4. Construction and Organization of Detection Probability Tables.- 6.5. Designing Three Strategies for the Search for Porphyry-Cu-Mo Deposits in the North American Cordillera Belt.- References and Selected Readings.- Seven Optimized Search for Four Types of Contact Metasomatic Deposits of the North American Cordillera Belt.- 7.1. General Geological Background.- 7.2. Field Detection Methodology.- 7.3. Probability of Detection of Cu-Fe Contact Metasomatic Deposits.- 7.4. Probability of Detection of Pb-Zn-Cu-Ag Contact Metasomatic Deposits.- 7.5. Probability of Detection of Cu-Mo-Au Contact Metasomatic Deposits.- 7.6. Probability of Detection of W-Mo Contact Metasomatic Deposits.- 7.7. Designing Three Strategies for the Detection of Four Types of Contact Metasomatic Deposits of the North American Cordillera.- References and Selected Readings.- Eight Detection of Ni-Cu Ultramafic Deposits of the North American Shield by Optimized Geophysical Surveys and Drilling Programs.- 8.1. General Geological Background.- 8.2. Field Detection Methodology.- 8.3. Statistical Modeling of Geometric Parameters of Ni-Cu Deposits.- 8.4. Construction and Organization of Detection Probability Tables.- 8.5. Designing Three Strategies for the Detection of Ni-Cu Deposits of the North American Shield.- 8.6. Detection Probability and Optimization Tables.- References and Selected Readings.- Nine Optimized Airborne and Ground Search for Volcanogenic Massive Sulfide Deposits of the North American Shield and Cordillera Belt.- 9.1. General Statement.- 9.2. General Geological Background: Volcanogenic Sulfide Deposits of the North American Shield.- 9.3. Field Detection Methodology.- 9.4. Statistical Modeling of Geometric Parameters of Shield.- Volcanogenic Sulfide Deposits.- 9.5. Construction and Organization of Detection Probability Tables for Shield Volcanogenic Sulfide Deposits.- 9.6. Design of Three Strategies for the Detection of Shield Volcanogenic Sulfide Deposits.- 9.7. Detection Probability and Optimization Tables for Shield.- Volcanogenic Sulfide Deposits.- 9.8. Geological Synopsis for Volcanogenic Sulfide Deposits of the North American Cordillera Belt.- 9.9. Statistical Modeling of Geometric Parameters of Cordillera Volcanogenic Sulfide Deposits.- 9.10. Construction and Organization of Detection Probability Tables for Cordillera Volcanogenic Sulfide Deposits.- 9.11. Designing Three Strategies for the Detection of Cordillera Volcanogenic Sulfide Deposits.- 9.12. Detection Probability and Optimization Tables for Cordillera Volcanogenic Sulfide Deposits.- References and Selected Readings.- Ten Designing Optimized Field Programs for the Detection of Mississippi Valley-Type Pb-Zn Deposits of the North American Arctic Paleozoic Platform.- 10.1. General Geological Background.- 10.2. Field Detection Methodology.- 10.3. Statistical Modeling of the Geometric Parameters of North.- American Arctic Deposits.- 10.4. Construction and Organization of Detection Probability Tables.- 10.5. Designing Three Strategies for the Detection of Arctic Mississippi Valley-Type Pb—Zn Deposits.- 10.6. Detection Probability and Optimization Tables.- References and Selected Readings.- Eleven Detection of Vein-Gold Deposits of the North American Shield by Optimized Ground Programs.- 11.1. General Geological Background.- 11.2. Field Detection Methodology.- 11.3. Statistical Modeling of Geometric Parameters of Vein-Gold.- Deposits.- 11.4. Construction and Organization of Detection Probability Tables.- 11.5. Design of Three Strategies for the Detection of Archean Vein-Gold Deposits of the North American Shield.- 11.6. Detection Probability and Optimization Tables.- References and Selected Readings.- Twelve Optimal Selection of Exploration Targets for Drill Testing.- 12.1. General Statement.- 12.2. Optimal Selection of Exploration Targets Based on Control Locations.- 12.3. Optimal Selection of Exploration Targets without Control Locations.- References and Selected Readings.- Conclusion.- Appendix: Measurement Conversion Table.- Author Index.- Listed Journals.