AUSQUEST has identified two new conductors from recent reconnaissance ground electromagnetic (EM) surveys within its Balladonia South and Dundas East projects in the Fraser Range region of Western Australia. Drilling of both targets is planned for the second quarter of 2015, subject to completion of further work to optimize drilling locations and access approvals.
The EM conductor within the Balladonia South tenement is about 40km east of Sirius Resources’ Crux prospect and is associated with a negative magnetic anomaly similar to the response over the Crux intrusion. The Crux prospect is the subject of diamond drilling by Sirius, which has reported “Nova-style host rocks containing disseminated and matrix sulphides” from the first diamond drill hole.
Negative magnetic anomalies, thought to reflect mafic/ultramafic intrusions similar to Crux, are evident within Balladonia South and were the focus of reconnaissance moving loop electromagnetic surveys (MLTEM) designed to search for massive sulphide mineralization associated with these intrusions.
A moderate-to-strong late-time (156.8m sec) EM response was found in survey block 5, closely associated with an east-south-east trending dyke-like intrusion interpreted to be up to several hundred metres thick. The EM target appears strike limited (about 800 metres) and trends parallel to the dyke, suggesting a close relationship with the cross-cutting intrusion. Modelling of the EM data suggests a plate-like target with moderate conductance and a shallow south-westerly dip.
High near-surface conductivities evident in the early-time data suggest deep weathering of the intrusion and invoke the possibility of a substantial ultramafic component within the underlying rocks.
No significant EM anomalies were detected within the Blocks 1 to 4 and Block 6. Infill EM surveying within block 5 was expected to commence in early April to fully outline the target and optimize drill sites ahead of planned drilling.
The EM target within Dundas East tenement, about 30km south of Crux, is associated with low order magnetic and gravity anomalies thought to reflect potential mafic host rocks within a dominantly sedimentary sequence. Soil sampling completed in 2014 located a number of elevated nickel and copper values associated with these anomalies.
Modelling of the EM data shows the target is about 600 metres long, dips to the south-west at about 60 degrees and occurs at depths of about 100 metres. Elevated nickel and copper soil assays partially coincide with the northern half of the anomaly. Drilling is planned to test this target once clearances have been obtained.