Rock Geochemistry in Mineral Exploration

Preface

Introduction

Part I. General Principles

Chapter 1. Geochemistry in the Exploration Sequence

Introduction

Principles Underlying Geochemical Exploration

Main Types of Geochemical Surveys

Sequence of Geochemical Exploration

Conclusions

Chapter 2. Crustal Abundance, Geochemical Behaviour of the Elements, and Problems of Sampling

Abundance of the Elements

Classification and Geochemical Behaviour of the Elements

Sampling

Chapter 3. Recognition of Geochemical Anomalies

Introduction

Background and Threshold

Spatial Distribution of Data

The "Law of Lognormality"

Population Partition

Anomalous Patterns

Soviet Interpretative Procedures

Conclusions

Part II. Regional Scale Exploration

Chapter 4. Regional Scale Exploration for Deposits of Plutonic Association — Discrimination Between Productive and Barren Intrusions

Element Concentration and Geochemical Specialization

Character of Frequency Distributions

Case Histories Based on Whole Rock Analyses of Felsic Intrusions

Case Histories Based on Whole Rock Analyses of Mafic Intrusions

The Use of Mineral Separates, Halogens, and Mineral-Selective Leaches

Rationale for the Approach

Measurement of Halogens and Water in Whole Rock

Halogens in Biotite

Distribution of Metals in Biotite and Feldspar

Sulphide-Selective Leaches

Conclusions

Chapter 5. Regional Scale Exploration for Deposits of Plutonic Association — Identification of Tin Granites

Introduction

Case Histories

Discussion of an Interpretative Procedure

Conclusions

Chapter 6. Regional Scale Exploration for Vein and Replacement Deposits

Introduction

Anomalies of More than 6 Km

Anomalies Of 3—6 Km

Anomalies Of 1—3 Km

Conclusions

Chapter 7. Regional Scale Exploration for Stratiform Deposits of Volcanic and Sedimentary Association

Introduction

Geology and Genesis of Massive Sulphide Deposits

Archaean Massive Sulphides of the Canadian Shield

Proterozoic Massive Sulphides of the Canadian Shield

Palaeozoic Massive Sulphides in New Brunswick

Massive Sulphide Deposits in Cyprus

Other Examples of Volcanic-Hosted Massive Sulphides

Massive Sulphides of Sedimentary Association

Conclusions

Part III. Local and Mine Scale Exploration

Chapter 8. Local and Mine Scale Exploration for Porphyry-Type Deposits

Introduction

Canadian Case Histories

U.S. Case Histories

Use Of Rubidium, Strontium and Potassium

Conclusions

Chapter 9. Local and Mine Scale Exploration for Vein and Replacement Deposits

Introduction

Logarithmic Decay Patterns

Surface and Weathered Bedrock Surveys

Techniques of Determining Dimensions and Distances of Veins

Conclusions

Chapter 10. Local and Mine Scale Exploration for Stratiform Deposits of Volcanic and Sedimentary Association — Precambrian, Proterozoic, and Kuroko Deposits

Introduction

Archaean and Proterozoic Deposits

Kuroko Deposits

Conclusions

Chapter 11. Local and Mine Scale Exploration For Stratiform Deposits Of Volcanic and Sedimentary Association — New Brunswick

Introduction

Description of the Deposits

Trace Element Geochemical Response

Major Element Halos

Analytical Considerations

Generalized Model and Interpretation of Geochemical Dispersion

Conclusions

Chapter 12. Local and Mine Scale Exploration for Stratiform Deposits of Volcanic and Sedimentary Association — Cyprus, Turkey, and Oceania

Cyprus Deposits

Turkish Deposits

Australian Deposits

The Wainaleka Deposit, Fiji

Conclusions

Part IV. Summary and Conclusions

Chapter 13. Synthesis of Geochemical Responses and Operational Conclusions

Introduction

Recognition of Productive Intrusions and of Halos Around Porphyry Deposits

Vein and Replacement Deposits

Volcanic-Sedimentary Massive Sulphides

Operational Conclusions

Appendix 1 — Crustal Abundance, Distribution, and Crystal Chemistry of the Elements (P.C. Rickwood)

Appendix 2 — Abundance of Elements in Common Rock Types

Appendix 3 — Probability Table for Required Number of Samples

Appendix 4 — List of Deposits and Mineralized Districts and Source of References for Geochemical Data

References

References Index

Subject Index