Grant: Alliance Grants

Zircon hosts a suite of geochemical indicators of Cu-fertile porphyry deposits and is commonly used to explore for porphyry copper deposits. Nevertheless, decision-making is hampered by a lack of quantitative interpretations, statistically robust data sets, or integration of multiple data sources. There are three major challenges with the use of zircon U-Pb geochronology data. The challenges are related to (1) the challenge of collecting statistically robust zircon geochronology data sets related to a) reproducibly separating heavy minerals from samples and b) the time and analytical costs of analyzing sufficient zircons; (2) generating robust interpretations of detrital zircon geochronology and geochemical data; and (3) integrating zircon data with other mineral indicators of fertility in a robust and statistically valid framework. We propose a three-year project to develop methods to accelerate data acquisition, reduce costs and improve the statistical robustness of zircon data sets. In parallel, this project will develop new, multivariate, quantitative methods to interrogate the zircon data sets and incorporate them into a multi-mineral and multi-proxy framework to aid exploration decisions. To address Challenge 1) we will test, compare, and validate several new approaches for more rapid and reproducible separation of heavy minerals from host samples. In parallel to the research on improved heavy mineral concentration methods, we will test methods of generating faster, statistically robust and less expensive assessment of detrital zircon U-Pb ages and mineral chemistry. We will provide robust interpretations of detrital zircon geochemistry and geochronology data (Challenge 2) by developing an unmixing approach to identify the proportion of zircons derived from prospective Cu porphyry intrusive rock upstream from a detrital mineral sample. To address Challenge 3 we will develop a multi-variate and multi-mineral unmixing algorithm based on Bayesian principles.