Key Highlights

  • RC drilling at Nabarlek North returned 1.7m at 1,116ppm eU3O8 from 168.8m and 2.3m at 920ppm eU3O8 from 184m, based on downhole Gamma readings with laboratory assays pending.
  • A new hyperspectral survey mapped an extensive illite alteration zone in sandstones along the north-westerly projection of the Nabarlek Fault Corridor.
  • Drilling at Sandfire found no significant uranium and no chlorite alteration next to the fault zone, so the target area was downgraded.

DevEx Resources Limited (ASX:DEV) published an exploration update on 6 October 2026 covering its 100%-owned Nabarlek Uranium Project in the Northern Territory. The announcement reports initial hyperspectral survey results along the Nabarlek Fault Corridor and the completion of first-pass drilling at four priority targets: Big Radon, KP, Sandfire and Nabarlek North. The work forms part of the first phase of a multi-year exploration plan, following the consolidation of tenements acquired from Alligator Energy Limited (ASX: AGE) and Rio Tinto.

Drilling campaign scope

The 2026 campaign totalled 40 holes for 11,050 metres of reverse circulation (RC) and diamond drilling. The drill hole table in the release shows that most holes at KP, Sandfire and Nabarlek North were logged as having no significant uranium intercept under the cut-off defined in the announcement, so the reported mineralised intervals come from a small number of holes.

Nabarlek North intercepts

Two RC holes returned uranium equivalent grades from downhole gamma probes. Hole NAR26012 (RC12) intersected 2.3 metres at 920ppm eU3O8 from 184 metres, including 0.8 metres at 1,361ppm eU3O8. Hole NAR26013 (RC13) intersected 1.7 metres at 1,116ppm eU3O8 from 168.8 metres. The company notes that these are calculated equivalent grades rather than chemical assays, and that laboratory results are still pending. Interval lengths are down-hole, as true widths are yet to be determined.

The mineralisation sits in a sub-horizontal zone within the footwall of the south-dipping Oenpelli Dolerite. DevEx says it may reflect uranium remobilised away from the original north-west fault target. A second traverse recorded a dislocation of the unconformity between holes RC16 and RC18, with gamma readings of up to 107ppm eU3O8 near the unconformity in RC18. That area remains open to the north-west.

KP and Sandfire results

At KP, drilling passed through roughly 100 metres of sandstone cover into altered chlorite-haematite basement rocks. Diamond hole NBDD26004 recorded gamma readings of up to 400 counts per second, equal to about 30ppm eU3O8, between 129 and 130 metres, although it did not intersect the interpreted KP fault zone. Alteration intensity increases to the north-west, and ground geophysics plus a new seismic survey, with results pending, will be used to refine targets.

At Sandfire, drilling tested the projected Angularli Fault Zone and found a silica-rich fault zone where predicted. However, the targeted unconformity and overlying McArthur Basin sandstone have been stripped away, and the absence of significant uranium and of chlorite alteration led the company to downgrade the target area.

Hyperspectral survey and tenement applications

The hyperspectral survey was flown in August 2026 over granted tenements, and the initial review mapped an extensive illite alteration zone within sandstones overlying the north-westerly projection of the Nabarlek Fault Corridor. DevEx describes the review as preliminary and says it highlights several kilometre-scale areas for field mapping and pathfinder sampling.

The release also reports progress on tenement applications. Traditional Owners have consented to the Northern Land Council negotiating access agreements, and anthropological surveys over the Mustang and Junction applications are complete. The company expects access to these targets, which also include Corsair and Skytrain, over the coming 12 to 18 months.

Interpretation behind the Nabarlek North targeting

The company says previous drilling at Nabarlek North focused on uranium associated with a north-west fault zone interpreted as the East Shear. Ground gravity and structural interpretation indicate this shear probably passes east of the historical Nabarlek Mine, which would place the more prospective Nabarlek Fault in an area tested only on 400 metre spaced traverses. DevEx describes that spacing as too broad to identify a high-grade Nabarlek-type deposit, and it targeted positions where the fault is interpreted to cross the Oenpelli Dolerite into basement schists beneath the McArthur Basin sandstones.