ROCKY MOUNTAIN MINERAL LAW FOUNDATION Science and Technology Series AN INTRODUCTION TO GEOLOGY AND HARD ROCK MINING By Dr. Willard Lacy Table of Contents A NOTE ABOUT THE AUTHOR ...................................................................................................................................... III LIST OF FIGURES ........................................................................................................................................................... V LIST OF TABLES .......................................................................................................................................................... VIII INTRODUCTION ............................................................................................................................................................. 1 PRINCIPAL REFERENCES FOR THE SCIENCE AND TECHNOLOGY OF GEOLOGY AND HARD ROCK MINING ................. 2 BASIC GEOLOGY ............................................................................................................................................................ 3 I. FIELDS OF BASIC GEOLOGY AND DEFINITION OF MINERALS.............................................................. 3 II. GEOLOGICAL PROCESSES .................................................................................................................. 5 A. IGNEOUS PROCESSES .................................................................................................................... 6 B. WEATHERING AND EROSION ........................................................................................................ 8 C. SEDIMENTATION .......................................................................................................................... 8 D. METAMORPHISM ......................................................................................................................... 9 E. TECTONIC PROCESSES .................................................................................................................. 9 F. MINERAL DEPOSITION .................................................................................................................. 9 III. GEOLOGICAL STRUCTURES .............................................................................................................. 11 A. IGNEOUS STRUCTURES ............................................................................................................... 11 B. SEDIMENTARY STRUCTURES ...................................................................................................... 11 C. TECTONIC STRUCTURES .............................................................................................................. 13 D. LANDFORMS ............................................................................................................................... 13 IV. GEOLOGICAL TIME SCALE ................................................................................................................ 13 V. ECONOMIC GEOLOGY ..................................................................................................................... 15 VI. DEFINITIONS .................................................................................................................................... 15 A. ORE ............................................................................................................................................. 15 B. WASTE ........................................................................................................................................ 18 C. CUT-OFF ...................................................................................................................................... 18 VII. ORE-FORMING PROCESSES ......................................................................................................... 18 A. Weathering and erosion ............................................................................................................. 18 B. Igneous/volcanic processes ........................................................................................................ 18 C. Sedimentation/diagenesis. ......................................................................................................... 18 D. Tectonic/metamorphic processes ............................................................................................... 22 VIII. CLASSIFICATION OF MINERAL DEPOSITS .................................................................................... 22 A. Titley’s classification ................................................................................................................... 27 B. Additional classifications ............................................................................................................ 27 IX. STRUCTURES OF MINERAL DEPOSITS .............................................................................................. 31 X. RECOGNITION ................................................................................................................................. 43 PROSPECTING AND EXPLORATION ............................................................................................................................. 44 I. MINERAL EXPLORATION .................................................................................................................. 44 A. OBJECTIVES ................................................................................................................................. 45 B. STRATEGIES ................................................................................................................................ 45 C. TACTICS....................................................................................................................................... 45 II. MINERAL LAND OWNERSHIP ........................................................................................................... 61 A. FEDERAL LANDS .......................................................................................................................... 61 B. STATE LANDS .............................................................................................................................. 61 C. PRIVATE LANDS .......................................................................................................................... 61 III. TRESPASS......................................................................................................................................... 62 EVALUATION OF MINERAL DEPOSITS ......................................................................................................................... 63 I. DEPOSIT EVALUATION ..................................................................................................................... 63 i A. EVALUATION OF EXPLORATION PROGRAM ............................................................................... 63 B. COST/BENEFIT ANALYSES ........................................................................................................... 68 C. ENVIRONMENTAL IMPACT ......................................................................................................... 68 D. ORE RESERVE/RESOURCE ESTIMATION ...................................................................................... 69 E. COSTS AND COST ESTIMATION ................................................................................................... 83 II. FINANCING ...................................................................................................................................... 85 FINANCIAL ANALYSIS .................................................................................................................................................. 91 I. FEASIBILITY ANALYSIS ...................................................................................................................... 91 A. OBJECTIVES ................................................................................................................................. 91 B. DETERMINATION OF CAPITAL COSTS ......................................................................................... 91 C. RISK ANALYSIS ............................................................................................................................ 92 II. MARKETING AND FINANCING ......................................................................................................... 92 A. PRODUCER PRICING ................................................................................................................... 94 B. EXCHANGE-BASED PRICING ........................................................................................................ 94 C. INDUSTRIAL MINERALS............................................................................................................... 95 D. MINERAL PRICES ......................................................................................................................... 95 III. FINANCING MINE DEVELOPMENT ................................................................................................... 95 METHODS OF MINING AND MILLING ......................................................................................................................... 98 I. MINING METHODS .......................................................................................................................... 98 A. SURFACE MINING