EL's 9022, 9023 and 9325 - Willieray Project Final Report for the period ending 3 September 1997

Abstract

The Willeray Group of tenements is located approximately 120 km north of Tennant Creek, NT, just west of the Stuart Highway. The area covers mid-Proterozoic sedimentary and subordinate volcanic rocks of the Tomkinson Creek Subgroup, within the Tennant Creek Block. It is suggested that this area represents the southern extension of the McArthur Basin, host to the HYC Zn-Pb-Ag deposit. Zircon dating confirmed an HYC equivalent age (1640 Ma). A GEOTEM survey was flown to cover the Willieray area where previous exploration had shown good prospectivity for SEDEX Pb-Zn-Ag mineralisation. Two 'priority one' anomalies were delineated along with a large number of low priority targets which coincided with both McArthur and Roper Group stratigraphy. Ground TEM was completed shortly after the GEOTEM survey on the two priority one anomalies. Subsequent drilling of these conductors intersected deep clay-rich zones of weathering and the high abundance of clay was interpreted as the source of the conductors. Due to the disappointing drill results it was decided that the other conductors (which also displayed similar characteristics, although less conductive) were not worth drilling. Therefore no further work is required within the Willeray area. 4 size fractions were collected from 24 stream sediment sites to follow up anomalies outlined by previous explorers. These earlier results were not repeated. The titles were subject to an airborne EM survey. Two conductors (WY1 & WY3) were followed up by ground EM, soils & RC/diamond drilling. The holes intersected ferruginous clay which has been interpreted as the source of the anomaly.