Striving to increase efficiency – doing more with less by working smarter to make discoveries while reducing its footprint and emissions – is how the Australian minerals exploration industry will thrive. TONY HESELEV reports
Driving efficiency in mineral exploration
Efficiency is the ability to avoid wasting materials, resources, energy, effort, time and money in delivering or producing a desired result.
Technological developments, such as those the MinEx Cooperative Research Centre (MinEx CRC) is working towards in its nine projects, are driven by efficiency.
These developments centre on:
- more productive, safer and environmentally friendly drilling methods to discover and drill-out deposits, including coiled tubing drilling technology
- new technologies for collecting data while drilling, bringing forward mine production, and
- drilling in under-explored areas of potential mineral wealth in Australia through a partnership of geological surveys and researchers, known as the National Drilling Initiative (NDI).
Adopting technologies proven in other industries
"The CRC now in its second year of a ten-year life, is not afraid to borrow from other industries, including defence, telecommunications and information technology, to adapt and apply ideas such as fibre-optic cables in downhole and surface exploration and computing advances to better process large amounts of data to enable 3D modelling for exploration," says Chief Executive Andrew Bailey.
A key part its work is helping the industry reduce its environmental footprint by developing more efficient drilling rigs.
RoXplorer® delivers efficiency in drilling
The CRC and its predecessor organisation1 developed the RoXplorer®, a lightweight, mobile drilling rig that uses coiled tubing technology, adapted from the petroleum industry.
Drilling with a continuous coil removes the need to connect and disconnect drill rods as a drillhole deepens, making it faster, cheaper and safer than conventional drilling – and reduces the environmental footprint by drilling smaller holes with a lighter and more mobile drilling platform.
The first generation RoXplorer was capable of drilling to a depth of 500 metres.
A second generation RoXplorer, which can drill to 1000 metres and has been fitted with additional fluid processing capability, will be tested in the field at Kapunda, South Australia, early next year. This follows field trials of the original RoXplorer in Nevada, Port Augusta and Horsham.
"The second generation RoXplorer®, has a longer coil and deeper reach as well as sensing and steerable drilling," Mr Bailey said.
"This is more efficient, more rapid and smaller footprint drilling that is a cheaper method of testing through thick cover sequences which traditionally have been very difficult to drill through."
RoXplorer® deployment in Australian geological surveys
The RoXplorer®, will be used in the South Australian and West Australian geological surveys' drilling and research programs next year as part of the NDI.
The South Australian drilling will focus on the Delamerian basement in the Murray Basin beginning in autumn.
The Western Australian drilling will begin in spring, focussed on unlocking greenfields terranes in the remote desert country in the east of the state.
These programs are expected to deliver significant pre-competitive data to the market, resulting in a better-informed exploration environment in Australia, and improve understanding of a wide range of mineral systems, including those associated with critical metals.
Looking for critical metals
Mr Bailey said the CRC's aim is to better understand the systems beneath the blanket of deeply weathered rocks and transported sediments that covers about three-quarters of Australia, to enable companies to explore for specific minerals including critical metals that will help deliver technological advances such as enhanced energy storage.
"Australia has a large percentage of critical metals but understanding where they are is key to be able to efficiently exploit them," Mr Bailey said.
"We need to develop an understanding of where these critical metals are so that we can meet society’s needs when required."
The world's largest mineral exploration collaboration
The $218 million MinEx CRC is the world's largest mineral exploration collaboration, bringing together a total of 38 industry, government and research organisations. Its work ranges from undertaking fundamental research to commercialising research projects.
CSIRO is a major research partner in the CRC, along with seven Australian universities.
CSIRO Principal Research Scientist Yulia Uvarova, who leads the MinEx CRC 'Data from Drilling' program, and her team are developing sensing technology based on laser-induced breakdown spectroscopy (LIBS).
The LIBS technology had been used to sense and analyse the relatively few elements found in alloys, pharmaceuticals and other non-geologic materials.
Downhole in situ chemical analysis technology
But Dr Uvarova's team is developing a downhole tool that is so versatile that it can sense elements across the periodic table and provide chemical analysis in situ.
"The conventional method is to extract the core and send it to the lab for chemical analysis," she says. "Of course, that takes time and is very costly, especially if you are drilling in remote areas.
"Our idea was to build a tool that can be deployed right after drilling the hole – maybe the same day – collect the downhole chemistry onsite through a deep, slim drillhole and get results almost immediately, providing practical information to geologists and drillers in real time."
Using LIBS downhole assay tool will require fewer drillholes, reducing rock cutting, grinding and crushing, and saving transport and fuel costs, although exploration companies will still want to send samples to the lab to verify the initial analysis.
The MinEx CRC also works to improve the efficiency of conventional drilling rigs by, for example, placing sensors on the rigs to measure and analyse flow and pressure data, and applying advanced seismic and petrophysics capabilities to the rigs.
"Not all advances can be giant leaps," Mr Bailey said.
"We've got to accept that drilling has been done in that manner for 150 years and we don’t expect to throw all that out at once and come in with a totally new technique."
1 The Deep Exploration Technologies (DET) CRC concluded in September 2018 at the end of its federal funding period