This PhD project by Cassady Harraden aimed to use Corescan™ data to extract geotechnical parameters from drill core, as well as determine which microanalytical techniques would be best used in conjunction with the Corescan™ system to assess gold and copper grain size. The grain size assessment included a contribution to TMVC project ‘T2b: Line scan technologies for drill core’ and a contribution to TMVC project ‘T2c: Integrating chemical and mineralogical data layers for element deportment’. Protocols to extract morphological and mineralogical geotechnical parameters have been developed. These parameters can then be modelled in 3D and integrated with the Cadia Mine’s current structural, geotechnical and geometallurgical models. Research in 2018 completed the reporting on the application of microXRF, LA-ICP-MS and LIBS to measuring Au and sulfide grain size.

Micro-XRF is suitable for measuring chalcopyrite grain size at a rate compatible with hyperspectral scanning devices (about 3 m/min). The sampling rate was approximately an order of magnitude too slow for an accurate measure of Au deportment, but we expect hardware development to close this gap within the next five years. LA-ICP-MS can measure Au deportment for fine grain Au deposits on samples extracted from the core trays. The laser-induced breakdown spectroscopy (LIBS) needs more work on the software to retrieve higher quality compositional data from the LIBS spectra. Cassady submitted her thesis in May and after corrections graduated in October 2018. A paper on the ‘Use of automated core logging technology for geotechnical assessment’ was submitted to Economic Geology in 2018 and is in review. On graduation Cassady was employed by one of the industry partners.

The goal of this PhD project by Cassady Harraden is to use Corescan™ data to extract geotechnical parameters from drill core, as well as determine which microanalytical techniques would be best used in conjunction with the Corescan™ system to assess gold and copper grain size. The grain size assessment work is, in part, a continuation of the 2016 project ‘T2b: Line scan technologies for drillcore’.

Protocols to extract morphological and mineralogical geotechnical parameters have been developed. These parameters can then be modelled in 3D and integrated with the Cadia Mine’s current structural, geotechnical and geometallurgical models. Research in 2017 has focussed on determining which microanalytical techniques could be used in conjunction with the Corescan™ system to adequately and rapidly assess gold and copper grain size. The current technologies being evaluated are: portable-XRF, micro-XRF, laser-induced breakdown spectroscopy (LIBS), and LA-ICP-MS.

In June, Cassady presented a paper on the methods for extracting fracture mineralogy from Corescan™ data at the AIG Drilling for Geology II conference in Brisbane, Queensland. She also presented a paper on assessing grain size using LA-ICP-MS line scan analysis at the 14th SGA Biennial Meeting in Quebec City, Canada. Cassady is expected to submit her thesis in mid-2018.

The goal of this PhD project by Cassady Harraden is to determine the correlation between Corescan™ data and measured deportment data, processing parameters and geotechnical conditions. Hyperspectral data will be used to determine functional proxies that will ultimately be built into predictive algorithms and applied to the mine-wide dataset to produce geometallurgical domains. These domains can then be modelled in 3D and integrated with the Cadia Mine’s current geologic, structural and geometallurgical models.

A paper on the geotechnical methods previously developed in this project was presented at GeoMet 2016 in Perth, with Cassady being co-recipient of the award for ‘Best Paper by a Young Scientist’.

Research has focussed on fine-tuning the protocols for extraction of geotechnical parameters, which was completed during the year. The integration of those parameters with alteration mineralogy will continue into 2017.

The goal of this PhD project by Cassady Harraden is to determine the correlation between Corescan™ data and measured deportment data, processing parameters and geotechnical conditions. Hyperspectral data will be used to determine functional proxies that will ultimately be built into predictive algorithms and applied to the mine-wide dataset to produce geometallurgical domains. These domains can then be modelled in 3D and integrated with the Cadia Mine’s current geologic, structural and geometallurgical models.

A major breakthrough was made late in the year, when the researchers developed a new tool for utilising automated core logging technology to extract geotechnical index parameters. The new tool has the potential to revolutionise geometallurgical data acquisition, replacing the laborious manual geotechnical logging procedures that currently form the industry standard, and allowing large volumes of consistent geotechnical data to be acquired through automated core logging. After a pilot study, the tool is now being up-scaled to enable it to be implemented during a major program of automated core scanning by Newcrest Mining and Corescan in 2016. Results of the pilot study will be released at the 3rd International Geometallurgy Conference in 2016.