Menzies/Goongarrie – Au
Menzies Gold Project Geological Summary
The Menzies greenstone belt divides at Menzies into a western section continuing to the northwest and an eastern section continuing northwards to Twin Hills. The greenstone sequence consists of a lower ultramafic formation to the west overlain by meta-sedimentary rocks which are overlain by mafic intrusives and extrusives to the east. Included in the greenstone belt are the major shear zones, the Menzies Shear Zone and the Moriarty Shear Zone, which impart a strong foliation and lineation to the underlying rock.
The Menzies Shear Zone can be traced south wards to the Bardoc Deformation Zone approximately 50kms south. Metamorphic grade is high in the amphibolite facies with porphyroblastic grain textures, marked schistosity and mineral lineations.
A southerly plunging fabric is apparent in the Menzies area, where well foliated basalts, sedimentary rocks, mafic and ultramafic contacts are economically significant. In general ore zones have shallow westerly dips and alteration assemblages, comprising biotite, silica, pyrrhotite, pyrite, galena, sphalerite, arsenopyrite and chalcopyrite are typical in areas of stronger gold mineralisation. Cross cutting features and felsic porphyry intrusives are also important in terms of hosting gold mineralisation. The figure below shows the tenements with major geological rock units.
Menzies is typically marked by extensive sub parallel historical gold workings along and proximal to the major shear zones and splays. Up until WW1, approximately 653,000oz was mined underground, mostly from the First Hit, Lady Shenton and Yunndaga underground mines. The Yunndaga Mine reached a maximum depth of 600 vertical metres. Since then, recent open cut mining in the 1990’s has delivered an additional 143,000oz with most of the ore being treated at the Paddington Gold Mine.
Since acquisition the Company has been systematically re-drilling and verifying the existence of all historic resources and ensuring reported resources are in accordance with the JORC Code. The Menzies Project currently contains an Indicated and Inferred JORC 2012 Compliant Mineral Resource Estimate of 2.42Mt @ 2.20g/t Au for 171,310oz above a 1g/t cut-off (refer ASX announcement dated 8 March 2016).
All lodes are open at depth and only limited by drilling.
Drilling by Intermin has focused on the Selkirk and Aspacia Prospects where very high grades have been intersected. Further drilling is required to generate Resources at these two key prospects.
Goongarrie Gold Project Geological Summary
The project is located on granted Mining, Exploration and Prospecting licenses forming a contiguous land package of over 20km of strike situated 40km south of Menzies in the Eastern Goldfields of Western Australia.
The project is located at the northern end of the Bardoc Tectonic Zone (“BTZ”), a major greenstone belt between Kalgoorlie and Menzies within the Kalgoorlie Terrane of the Archaean Yilgarn Craton. The tenements border the western edge of the BTZ with all deposits on or adjacent to a major NNW trending strike parallel shear zones varying in intensity from 20-200m wide. This trend continues to the Company’s Menzies gold project area to the northwest.
The Goongarrie gold project was first mined underground when the area was discovered in 1893 and modern mining and exploration was conducted in the 1980s by Julia Mines Ltd leading to the completion of 4 shallow oxide open pits that produced ~35,000 oz from shallow open cut mines until 1989. Exploration has been conducted by a number of small companies since with the most recent work in 2011/12 by Cove Resources demonstrating the potential for further mineralisation both along strike and below the very shallow historic mines.
Recent drill intercepts from the Caledonian prospect returned:
- 21m at 3.5g/t Au from 33m
- 43m at 1.6g/t Au from 71m
- 4m at 14.9g/t Au from 38m
- 57m at 1.23g/t Au from 31m (incl. 3m at 7.2g/t)
- 3m at 12.9g/t Au from 10m
- 22m at 2.0g/t Au from 52m
Further to the South within the prospect area is the Goongarrie Lady deposit which has a JORC 2012 Compliant resource of 0.27Mt @ 2.9g/t Au for 23,900oz.