2000 Annual Report - Heron Resources Limited

Operations Review
2.0 Continued
Edjudina Prospect
The prospect area including the Oak Well tenement group covers a very complex shear zone into which syn- and
post-tectonic granitoids have been emplaced. Deformation in the region has been taken up as ductile shears in the
greenstone belts, as brittle-ductile structures in granitoids, and locally as a late stage rift basin into which the Yilgangi
Conglomerate was deposited.
The syntectonic granitoids are gold-mineralised, including gold mining centres at Yarri (brittle structures) and Porphyry
(ductile mylonite zones). The Oak Well Shear Zone is characterised by an elongate composite granitoid hosting
remnants of basalt and felsic to intermediate schist. A post-tectonic gabbro is locally emplaced into the Shear Zone.
Recent exploration has confirmed the area to be prospective for both base metals and gold. Highly anomalous Cu,
Zn, Pb and As values are associated with chert and gossanous schists within a magnetic intermediate schist unit.
This zone is also anomalous for gold, with gold in soil to 1,900ppb, and gold in rock chips to 46.8g/t.
Exploration by Heron and then Croesus has included target generation, field mapping, and Aircore and RAB drilling.
Drill target areas were generated using detailed aeromagnetic data, followed by regolith mapping and field
reconnaissance.
Table 12 - EDJUDINA LAVERTON JOINT VENTURE
Oak Well Drilling Summary
Tenement Drill Type Holes Metres Samples
E31/190 RAB 10 131 34
E31/233 RAB 9 455 104
E31/234 RAB 10 340 78
E31/235 RAB 51 296 134
E31/288 RAB 54 3,096 677
E31/288 Aircore 8 527 121
E31/311 RAB 75 3,324 733
Project Total 217 8,169 1,881
Photo: Simon Gobbett (Project Geologist) and
Alan Rudd (Senior Geologist). This year, Simon and
Alan added about 50 million tonnes of high grade
laterites to their discovery record.
Two campaigns of drilling were completed which included 217 holes for 8,169 metres within the Oak Well group:
Table 13 - EDJUDINA LAVERTON JOINT VENTURE
Oak Well Drilling Significant Assays
Hole ID North East From To Intercept Grade Geology
m m m m m g/t Au
ENRB088 22,400 21,200 25 30 5 0.55 Clay-sericite saprolite, 2% quartz veining
49 52 3 0.23 Sheared volcaniclastic schist
ENRB110 23,300 20,600 45 55 10 0.20 Foliated clay-sericite felsite
Varden Prospect
A RAB program was completed on the Varden Prospect located 50km north of Laverton, to test low-tenor soil gold
anomalies. A total of 27 holes for 1,108m were completed. Rock types encountered include black shale, chloritealtered
quartzite, serpentinite and lesser basalt, dolerite, porphyry, felsic schist and BIF. Chlorite and sericite were the
dominant alteration styles, with silica and carbonate alteration associated with gold anomalism.
Photo Strip: After a good rain or two, these scarifying furrows become verdant with annuals. In a year or so, the saltbush
is back, and then the acacia understorey.
‘The Water Holes’ Andrea Munmurrie “There was lovely green water and on the top of the green water
there was brown water.”
page 24
Heron Resources NL
Annual Report 2000