b'What lies beneath revisitedFeaturethe conductivity, a relationship expected to be observed. However, Emerson did not address the issues relating to the formation of chalcocite and supergene enrichment, as was done by Alpers and Brimhall (1988). Also, Alpers and Brimhalls ideas on how the supergene gets upgraded appear to be more suggestions than well-documented theories. More work needs to be done to properly understand this mechanism.The argument could be made that this sort of study is too late to have any real impact on exploration best practice, the assumption being that most supergene deposits have already been found. However, whilst all shallow terrains may have been explored, covered areas unsuited to conventional geological mapping and geochemical exploration techniques are still potentially prospective.Figure 10.Crone DEEPEM coverage over shallow portion of Rosario veinThe more important conclusion is that a signi\x1dcant system (Wilt 1991). petrophysical attribute, one that could help explorers map and de\x1dne economic copper resources, has largely been ignored was a lack of petrophysical assessments that allowed thefor 100 years. While a renaissance in exploration for porphyry observed conductivity to be tied back to chalcocite per se,copper deposits appears to have occurred in the 1990s, little even though there was an extensive history of laboratorystudy of the phenomenon of conductive supergene copper work and some \x1deld work (Nelson 1991) that showed thatdeposits appears to have happened since then. My closing chalcocite is conductive. The major recent developmentquestion is, if the chalcocite story slipped under the fence, what in this \x1deld was the work of Don Emerson (Emerson 2021).other potentially important petrophysical relationships has the Don was able to show that as density increased, so didexploration community missed?Figure 11.3D view of Rosario vein system at depth; Xstrata Copper 2006.49 PREVIEW DECEMBER 2023'