Porphyry copper deposit model: Chapter B in Mineral deposit models for resource assessment
.1 Summary of Porphyry Copper Deposit Model .1 Associated Commodities and Deposit Types .1 Regional Environment .1 Physical Description of Deposits .2 Geophysical Characteristics .3 Hypogene Ore Characteristics .3 Supergene Ore Characteristics .4 Hypogene and Supergene Gangue Characteristics .4 Hydrothermal Alteration .5 Geochemical Characteristics .6 Petrology of Associated Igneous Rocks .7 Theory of Ore Deposit Genesis .8 Sources of Fluids .8 Controls on Permeability and Fluid Flow .8 Chemical Transport and Transfer Processes .9 Heat Transfer Processes .9 Pressure Gradients .9 Wall Rock Reaction and Ore Mineral Deposition Processes .9 Relation between Alteration, Gangue, and Veins .10 Geoenvironmental Features .10 Porphyry Copper Deposit Exploration and Resource Assessment Objectives and Guides .10 Broader Implications, Societal Relevance, and Knowledge Gaps of Porphyry Copper Deposits .10 A. Introduction..11 B. Deposit Type and Associated Commodities .11 Name .11 Synonyms .11 Brief Description .13 Associated and Transitional Deposit Types .14 Primary Commodities .14 By Product Commodities .14 Trace Constituents .14 Example Deposits..14 C. History of Porphyry Copper Deposits .14 D. Regional Environment .15 Geotectonic Environment .15 Temporal (Secular) Relations .18 Variations Through Geologic Time .18 Variation Within Magmatic Cycles .18 Duration of Magmatic Hydrothermal Systems that Form Porphyry Copper Deposits .18 Relations to Structures .21