The Nabarlek Project comprises the 100% Uranium Equities held Nabarlek Mineral Lease (MLN 962) which contains the historic and highly profitable Nabarlek Mine and the surrounding exploration licences held in joint venture with Cameco Australia Pty Ltd (UEQ right to earn 100%).
The tenements are contiguous and together cover more than 500 km2 in the heart of the Alligator Rivers Uranium Field, Northern Territory (Figure 1).
The Alligator Rivers Uranium Field is a world class uranium province which is analogous to the Athabasca Uranium Province, Canada in terms of uranium endowment. In contrast to the Athabasca, the Alligator Rivers Uranium Field is in the early phase of its exploration history, having received less than 1/10th of the exploration expenditure of its Canadian counterpart.
The Alligator Rivers Uranium Field is host to the major operating Ranger Uranium Mine and the large Koongarra, Jabiluka and Nabarlek Deposits (Figure 1). The Field’s mineral endowment, including mined resources, exceeds 500 Mlbs U3O8.
The uranium mineralisation in the main mineralised centres in the Alligator Rivers Uranium Field, as evidenced in the Ranger – Jabiluka area, occurs as clusters of structurally controlled deposits over strike distances of 2 – 6 kilometres. The Company believes the Nabarlek Project has the potential to discover a similar cluster of of mineralised zones proximal to Nabarlek.
The Alligator Rivers Uranium Field is one of the most prospective terrains in which to find high grade, world class uranium deposits in Australia.
West Arnhem Joint Venture
The West Arnhem Joint Venture was formed in 2007 to explore the Exploration Licences surrounding the Nabarlek Mineral Lease.
Cameco Australia Pty Ltd and Uranium Equities are parties to the joint venture, holding 60% and 40% joint venture interests respectively. In September 2012 the Company announced it had secured the right to move to 100 per cent ownership in the West Arnhem Joint Venture tenements under the following terms:
- Uranium Equities to spend $2 million over 48 months to complete the acquisition of Cameco’s 60% interest bringing Uranium Equities’ total ownership to 100%;
- If Uranium Equities elects to withdraw before acquiring a 100% interest, it will revert to its 40% contributing interest in the WAJV; and
- Cameco retains the right to ‘Claw Back’ to a 51% interest in the project on delineation of a Measured and Indicated JORC Compliant Resource of greater than 50 million pounds U3O8.
Historical uranium exploration within the joint venture area resulted in the discovery of a number of prospects based on airborne radiometric anomalism. Drilling has been undertaken at a number of prospects with anomalous, and in some cases, significant uranium mineralisation being intersected (N147, SMLB, U40 and Coopers Prospects).
A number of significant intercepts have been encountered at the U40 and Coopers Prospects (Figure 2).
The U40 Prospect is located 10km east-north-east of the historic Nabarlek Uranium Mine within the north-northwest trending Quarry Fault Zone (QFZ) which extends over several kilometres (Figure 2). The QFZ has been identified as a similar prospective parallel structural zone to the Nabarlek Structural Corridor. A detailed ground-based gravity survey has been completed over the entire strike extent of the QFZ.
RC drilling in 2010 intersected high-grade uranium mineralisation on the sheared contact between schists and quartzites within basement sequences. A follow up diamond drilling program confirmed the grades and widths with twin and scissor holes of NAR7389 returning the following intersections:
Twin Hole NAD7492 6.8m @ 6.71% U3O8 from 75m(1); and
Scissor Hole NAD7493 4.8m @ 1.85% U3O8 from 80.4m(1).
The lithologies encountered in the drill holes are extremely altered, sheared and deformed. Mineralisation occurs as pitchblende in massive blebs hosted within a highly chlorite altered rock.
The 2011 drilling program targeted possible extensions and intersected additional mineralisation in the hanging wall close to where the unconformity is intersected by the fault. This intersection is associated with a zone of clay alteration and includes the following intercept:
NAD7504 1.85m @ 0.35% U3O8 from 44.35m(1)
A 3D geological model was produced to assist with interpretation of known geology and mineralisation at the U40 Prospect. While the 3D model and drilling completed to date has demonstrated that the strike potential of the current zone of high grade mineralisation is limited, the company still believes the Quarry Fault Zone has the potential to produce additional quality exploration targets.
Laboratory assay results have also revealed that the uranium mineralisation is associated with elevated levels of gold, copper, palladium and platinum and anomalous heavy rare earth elements. Results include:
7.3m @ 1.68% Cu from 74.5m(1)
4.5m @ 0.91g/t Au from 76.5m(1)
1.5m @ 0.54g/t Pd and 0.24g/t Pt from 78.5m(1)
8.3m @ 2.12% Cu from 77.4m(1)
3.1m @ 6.89g/t Au from 82.1m(1)
2.6m @ 1.57g/t Pd and 0.96g/t Pt from 82.6m(1)
The high-grade intercepts remain the most significant recorded to date in the Nabarlek Project area outside the old Nabarlek Mine and reinforce the outstanding exploration potential for high-grade uranium deposits comparable to the Nabarlek Deposit.
The Coopers Prospect is located 2.4km east of the Nabarlek Mine and 800m east-north-east of the N147 Prospect, close to the south-east corner of the Nabarlek Mineral Lease. RC drilling in 2010 targeted a uranium bedrock geochemical anomaly previously defined by aircore drilling. Results include:
NAR7386 23m @ 0.20% U3O8 from 40m(1)
Uranium Equities’ current interpretation of the geological setting in the vicinity of drillhole NAR7386 suggests that there is a possible faulted offset position for dolerite-hosted mineralisation to the west.
Diamond drilling at the Coopers Prospect in 2011 intersected mineralisation within the Oenpelli Dolerite in one of the two holes drilled. Final independent laboratory assay results from the drilling program were received. Results include:
NAD7496 20m @ 0.22% U3O8 from 40.5m(1)
Strong hematite and chlorite alteration is associated with the mineralisation and occurs in the underlying basement rocks opening up the potential for hidden unconformity related mineralisation below the dolerite sill.
During the 2008 field season RC drilling was undertaken at the N147 Prospect which lies within the Nabarlek structural corridor close to the southern boundary of the Mineral Lease. The N147 Prospect had been the subject of historical drilling with discontinuous ore grade mineralisation being intersected.
Drilling by the joint venture in 2008 improved continuity and established the presence of a significant body of mineralisation. Ore-grade intercepts included:
NARD6017 21.1m @ 0.37% U3O8 from 115.1m(1)
NAR6318 34.0m @ 0.12% U3O8 from 109m(1)
NAR6320 14.0m @ 0.17% U3O8 from 118m(1)
Nabarlek Mineral Lease
The Nabarlek Uranium Deposit was discovered in 1970 by Queensland Mines Pty Ltd. Ore was mined and processed in the period from 1979 – 1988.
The last major phase of exploration carried out by Queensland Mines Pty Ltd was completed in 1984.
Uranium Equities Limited acquired Queensland Mines Pty Ltd in 2008. The Company is operating under an approved Mine Management Plan and access authorisations by the Traditional Owners. Although the site has been substantially rehabilitated, a bond has been established with the Northern Territory Government totalling $1.5 million to cover legacy rehabilitation issues. A program of rehabilitation has been initiated and progressively the bond will be reduced until regulatory release is achieved.
Regionally the Nabarlek Deposit lies within a northwest trending structural corridor, a complex array of faulting, shearing and low angle thrusts, which extends over several kilometres across the Mineral Lease and the surrounding Cameco – Uranium Equities West Arnhem Land Joint Venture tenement.
The Nabarlek Uranium Mine, which was a small deposit with a very high net value, producing 24Mlbs at an average grade of 1.84% U3O8 from a mineralised zone only 200m long and to a depth of 70m.
Uranium Equities has identified a significant new exploration target beneath the historical mine. The target, which was identified following a review of the geometry and alteration vectors, represents a potential offset extension of the Nabarlek orebody at depth.
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(1) Samples were sent to Northern Territory Environmental Laboratories Pty Ltd in Darwin for sample preparation and multi-element analysis. Samples undergo mixed four acid digest with an ICP-MS (Lab Code G400M) or ICP-OES (Lab Code G400I) finish depending on the element. A split of each sample pulp is sent for Au, Pd and Pt analysis using 50g Fire Assay with an ICP-MS or ICP-OES finish (Lab Code FAPMM). Intercept calculations can include up to 2 metres of internal dilution. Intervals reported are downhole widths and may not represent true widths of mineralisation. Cut-off values used for intercept calculations are 0.10% U3O8. Refer ASX Announcement dated 11 September 2012 for a full listing of drill results.