ASX Release: 7 February 2011Level 3, 1060 Hay St West Perth WA...

ASX Release: 7 February 2011
Level 3, 1060 Hay St West Perth WA 6005 Ph: +61 8 9321 9680 www.thundelarra.com.au
PO Box 7363 Cloisters Square WA 6850 Fax: +61 8 9321 9670 [email protected]
ABN: 74 950 465 654
Thundelarra is pleased to report that SRK Consulting has calculated a maiden JORC compliant resource
for the Thunderball Uranium Deposit at the Hayes Creek Project in the Northern Territory.
The resource estimate is based upon chemical assay data from 16 diamond and 39 reverse circulation
drill holes completed at Thunderball since the deposit was discovered by Thundelarra in late 2008. All
drill sample data was aggregated into four metre composites prior to modelling. All data composites with
a grade above 4,000 ppm were cut to that level. Resource estimates were then calculated at lower cut-off
grades of 200 ppm U3O8 and 400 ppm U3O8 for each of the two parallel zones of mineralisation, as
presented in the table below.
Thunderball has returned a number of exceptionally high grade drill intercepts, however the current drill
hole spacing is considered to be insufficient to prove continuity of this very high grade mineralisation.
Consequently a cautious approach has been taken to the classification of the resource and a top cut
applied to limit the influence of the high grade intercepts. The 4,000 ppm top cut affected five data
composites that had uncut average grades of up to 76,000 ppm U3O8 and disproportionally increased
contained metal by 200%. The uncut model comprises 775,000 tonnes at an average grade of 3,196 ppm
U3O8 for 5.5 million pounds of U3O8 (400 ppm U lower cut).
Geological modelling associated with the resource estimation has highlighted the potential to identify
repetitions of the existing mineralised zones at Thunderball. In particular the contact between the Gerowie
Tuff and Zamu Dolerite, approximately 70 metres stratigraphically below the Lower Zone resource, is
considered a priority target.
The declaration of an inaugural resource at Thunderball is an important milestone in development of
Thundelarra?s Hayes Creek Uranium Project. Five prospects at Hayes Creek have now returned
significant drill intercepts and in 2011 the Company will focus drilling on these targets with the aim of
upgrading one or more to resource status. Drilling will also be carried out at Thunderball to test for
repetitions of mineralisation at depth and along strike from the current resource. The Company?s
objective is to define sufficient uranium resources within the project area to justify establishment of a
central processing facility that can treat ore from several satellite deposits.
The Thunderball deposit is situated on Exploration License EL23431. Thundelarra has a 70% interest in
the uranium rights on EL23431 in joint venture with Crocodile Gold Australia Pty Ltd.
THUNDERBALL URANIUM DEPOSIT MAIDEN JORC RESOURCE
Tonnes
Grade
(ppm U3O8)
Contained Metal
(pounds U3O8)
Tonnes
Grade
(ppm U3O8)
Contained Metal
(pounds U3O8)
Lower Zone 848,000 907 1,696,000 795,000 945 1,656,000
Upper Zone 207,000 343 157,000 34,000 434 33,000
Total Inferred Resource 1,056,000 796 1,853,000 829,000 924 1,689,000
Thunderball Uranium Deposit Inferred Resource
200 ppm U3O8 Cut off Grade 400 ppm U3O8 Cut off Grade