What is aircore drilling? Aircore drilling is a shallow exploration drilling method that uses compressed air and a dual-tube system to bring pulverised rock samples to the surface. It’s fast, low-cost, and ideal for early-stage exploration.
If you’re mapping out shallow geology or testing targets before committing to deeper drilling, aircore is a go-to method.
A quick history Aircore drilling was developed in Australia in the 1960s to handle soft, unconsolidated ground. Since then, the method has evolved into a popular technique for cost-effective mineral exploration across the globe, especially in dry, sandy terrain.
How it works Aircore drilling works using a dual-tube reverse circulation (RC) system. Compressed air is pumped down through the outer tube of the drill string, creating enough pressure to force the loose drill cuttings back up through the inner tube.
At the bottom, a blade or tungsten bit cuts through soft or weathered ground as the drill rotates. Because the samples are carried up inside the inner tube rather than along the outside of the hole, they’re far less likely to be contaminated, making aircore more reliable than conventional open-hole methods for shallow exploration.
When and why you’d use aircore Aircore is best for:
Shallow drilling – typically up to 100 metres deep Soft or unconsolidated formations – like sands, soils, and weathered rock Scoping geology before committing to RC or diamond drilling Broad regional exploration where speed and cost are key It’s fast and cost-effective, and provides good sample recovery for soft ground. Plus, aircore drilling can help minimise sample contamination.
What aircore can’t do Aircore isn’t a one-size-fits-all solution. Limitations include:
Not suitable for hard rock formations (bit wear or refusal) Doesn’t deliver continuous core – only chip samples Less accurate for detailed geological logging or structure If your targets sit deeper or in hard rock, you’ll need to switch to RC or diamond .
Aircore vs RC vs diamond drilling
Feature
Aircore
RC
Diamond Drilling
Depth
Up to ~100m
Up to ~400m
>1000m
Sample Type
Pulverised cuttings
Pulverised cuttings
Solid core
Ideal For
Shallow, soft ground
Medium-depth, mixed ground
Deep, detailed geology
Speed & Cost
Fast & low-cost
Moderate
Slow & expensive
Contamination Risk
Low
Moderate
Very low
Safety and environmental considerations Like any drilling method, aircore must be done safely and responsibly. Key considerations:
Dust suppression – compressed air can generate fine dust, so dust control is criticalNoise – lightweight rigs reduce some noise impact, but controls are still neededSite access – smaller rigs mean less ground disturbanceFeatured Australian aircore drillers Here are a few aircore drilling contractors operating across Australia:
Precision Drilling Australia Known for modern rigs and over 25 years of experience, Precision supports aircore, RC, and diamond programs across WA, SA, and the NT. Precision Drilling Australia .
Bullion Drilling A family-owned company offering aircore, RAB, and RC drilling with flexible, customer-first programs.here
Want to find more aircore contractors? At CorePlan, we work closely with a number of aircore drill contractors to help manage their drilling business needs. To make it easier to find them, we’ve created The Ultimate Drill Contractor Directory which covers where each contractor operates, how many rigs they have, what types of drilling methods they utilise and even what sets their company apart so we can match up the best partnership for the job.
Visit the CorePlan Drill Contractor Directory for a full list of aircore drill contractors
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