Few universities around the world teach applied geochemistry in a way that equips graduate geologists with the knowledge and skills they will need in mining and exploration.
I have asked companies for permission to use their assays to demonstrate some of the type examples of magmatic and hydrothermal chemical processes in various ore deposits.
Los Andes has given us access to a subset of data from the Vizcachitas porphyry Cu deposit. This is in the same belt and same age as Rio Blanco-Los Bronces, Los Pelambres and El Teniente. This data very clearly demonstrates the magmatic processes in a porphyry Cu system. The first exercise shows how to use immobile trace element geochemistry to chemically fingerprint different lithologies and then map fractionation in the porphyries. Rio Tinto has given us access to a subset of data from a porphyry Cu prospect in the western USA. This porphyry has almost the full spectrum of alteration types seen in porphyry Cu environments. Exercise 2 shows how to classify the alteration types using the major element analyses. Exercise 3 compares the classification of alteration from assays with SWIR data from Corescan. Exercise 4 is a demonstration of the CODES (Tas Uni) excel-based program that converts weight% of elements to weight% of minerals.
The exercise1 data is provided as an excel file. The data for exercises 2 to 4 are provided as ioGAS files in the zip folder.