The transport and deposition of metals in hydrothermal fluids is dependent upon several variables te

1
Mineral Exploration III Geochemical Modeling of
Hydrothermal Systems

• The transport and deposition of metals in
  hydrothermal fluids is dependent upon several
  variables temperature, salinity, pH, oxygen
  (hydrogen) fugacity (?O2) ?S content of the
  fluid
• Variations in these parameters give rise to the
  wide spectrum of fluids responsible for
  hydrothermal ore deposits
• Geochemical modeling of fluid compositions is
  required to fully understand the transport and
  depositional processes operating in hydrothermal
  fluids
• Accurate geochemical models can assist in mineral
  exploration

2
Static Dynamic Geochemical Modeling

• Static models
• These conventional modeling techniques involve
  the construction of activity diagrams that are
  used to interpret the likely conditions of ore
  formation
• They are essentially frozen slices in P-T-X space
• In conjunction with detailed petrographic, fluid
  inclusion and stable isotope research, static
  thermodynamic modeling helps us to predict the
  spatial and temporal evolution of hydrothermal
  ore deposits
• Using simple balanced equations activity
  diagrams can help to determine mineral
  paragenesis, the chemical species in soln,
  transporting agents for metals models for ore
  depn
• However, static models require several activity
  diagrams to account for different P-T-X
  conditions in an evolving hydrothermal system

3
Useful Resources

• Web-resources
• Geochemistry Web Links
• On-Line Manuals
• Geol Sci 455 Chapters
• Exploration GEOCHEMISTRY
• GEOCHEMISTRY LINKS
• The Geochemical Society
• Geochem Online Manual
• Geochem Resources
• Texts
• Evans, A. M. 1995. Introduction to Mineral
  Exploration. Blackwell Science.
• Govett, G. J. S. 1983. Handbook of Exploration
  Geochemistry series. Elsevier.
• Evans, A. M. 1997. Introduction to Economic
  Geology and its Environmental Impact. Blackwell
  Science.