Porphyry deposits: genetic models using hyperspectral imagery data of drill core for exploration and mining applications

摘要

The identification of alteration minerals and their chemical composition calculation, along with characterisation of mineral textural relationships, can be effectively completed with the use of hyperspectral drill core imaging. Successful interpretation of hyperspectral drill core imagery, in combination with geological, geochemical and geophysical inputs, can lead to an expansion of current mineral resources, optimisation of mine processes, as well as future delineation of new green-field districts. In most ore deposits, alteration minerals are related to the chemistry of the mineralising fluids and are easily identifiable by spectral characteristics in the VIS-SWIR wavelength range. These include minerals such as mica-, amphibole-, carbonate-, chlorite-, iron oxide-, kaolinite-, smectite-, sulfate- and tourmaline-species. High resolution hyperspectral images, such as those collected by the Corescan multi-sensor platform, assist in capturing a higher amount of pure mineral pixels and enhance the interpretation of mixed pixels by having access to spectral data from neighbouring mineral grains. Additional advantages of 2D hyperspectral imaging include characterisation of texture and mineral associations.