The Epithermal and Mesothermal Gold Prospectivity modelling projects carried
out by Crown Minerals provided explorers in New Zealand with a new compilation
of historical exploration data combined with new geological information from the
GNS QMap 1:250,000 scale mapping project. These data were used to produce
predictive mineral potential maps for gold mineralisation in New Zealand. The
aim of these projects, to stimulate mineral exploration and investment in
exploration, has been successful with eight new companies acquiring new tenement
positions and committing significant exploration expenditure to exploring in New
Zealand in the coming years.
The projects were done at a national scale and consequently not all
exploration data were compiled into the prospectivity models. Several of the new
companies recognised the value of the prospectivity modelling work and committed
exploration funds to continue the modelling process. They recognised a need to
compile the remaining data and run the models again to allow detailed
exploration targeting.
Detailed data compilations including digitising historic exploration stream
sediment sample, rock chip sample, soil sample and drilling data has been
completed. New models have been completed in Otago for mesothermal gold
mineralisation and in the Coromandel and Northland for epithermal gold. The new
models have been compared with the original regional scale models and used to
target prospect scale exploration. This work has allowed exploration models for
epithermal and mesothermal mineralisation in New Zealand to be refined. More
importantly this work has identified significant areas with potential to host
gold mineralisation with little or no systematic geochemical data including soil
sampling or drilling. Exploration work programs have been designed to acquire
these missing data and exploration funds have now been committed to test the
areas highlighted by the prospectivity modelling.
In summary, the Epithermal and Mesothermal Gold Prospectivity modelling work
has successfully attracted new investment and ideas to the exploration scene in
New Zealand. The projects had an estimated cost of NA$250 000 and will in the
next two years, just through exploration expenditure, attract more than NZ$10 M
in investment. If a mine is discovered the return on investment will be
considerably greater.