Alteration Mapping

In broad alteration systems such as epithermal and porphyry systems infrared spectral data from PIMA, ASD or Hychips can be used to describe and map the distribution of various alteration mineral assemblages (eg. smectite, chlorite, biotite, illite, muscovite, kaolinite, dickite, pyrophyllite, alunite etc.).

In addition, trends in mineral crystallinity and composition can also be identified in the spectra and can be very important indicators in these systems when looking for vectors towards higher temperature parts of the system.

Large data sets of PIMA, ASD, HyChips spectra can be compiled quickly and at low cost allowing an in-depth evaluation of the alteration system to be carried out providing:

• Vectors toward prospective parts of the alteration system
• Consistent and objective logging and mapping of major alteration facies
• The discrimination of different phases of the same mineral, based on variations in composition and/or crystallinity. This allows discrimination of the signatures of overprinting and background mineralogies from the alteration mineralogies