CSIRO has introduced the AuScope National Virtual Core Library (NVCL), a digitised collection of 10 million metres of drill core estimated to be archived in warehouses around Australia.
The cores are analysed using HyLogger, an automated sampling system that generates digital images, surface profiles and mineralogical interpretations.
The data is then compared and mapped with other adjacent cores to build a bigger picture of what’s underground in a given area, providing ‘a new set of eyes’ to geologists, so they can map mineral composition rapidly and objectively.
According to the CSIRO, drilling costs each drill hole costs around $200 to $300 per metre of core, with one drill core sample costing potentially hundreds of thousands of dollars.
CSIRO honorary fellow Jon Huntington said, “In a good year, the Australian exploration industry can spend in the order of half a billion dollars per annum drilling holes.”
Maximising results from previously drilled cores is essential. The resource has valuable information to help explorers better target prospective areas, which decreases reliance on drilling and impact on the environment. It also provides insight into future exploration programs.
“In the past, exploration was often quite commodity and spatially focused; a nickel miner would look intensively for nickel in conventional nickel terrains but not consider other commodities,” Huntington said.
“The modern concept in exploration is the examination of an entire mineral system, which has multiple spatial and geological age dimensions possibly containing multiple commodities.
“Traditionally, if you found a vein of gold, you focused on that. Today you would be interested in the five to ten kilometres around that vein and even other commodities – a mineral system is a much bigger target than an orebody.”
Northern Territory Geological Survey mineral exploration geologist Belinda Smith said the NVCL aimed to characterise the top one-to-two kilometres of the Australian continent
“With the NVCL, we can go back to the old drill cores and ask, ‘What are the near-miss indicators?’ I can now interpret the non-economic, alteration minerals in a drillcore that suggest I am in a good place – whether it’s 100 metres, a kilometre or even five kilometres away,” Smith said.
The NVCL is an open-access resource for anyone in the world.