Being located adjacent to Sandfire Resources' DeGrussa project area, Ausgold's Doolgunna Station project is prospective for similar volcanogenic massive sulphide (VMS) copper-gold mineralisation
An independent interpretation of Ausgold's project area by SRK Consulting has confirmed the Company's tenement includes the prospective Narracoota Volcanics (the geological unit hosting the neighbouring DeGrussa one bodies). This interpretation similarly showed that Ausgold's project area covers the continuation of the Jenkins Fault, which appears spatially associated with the DeGrussa / Conductor copper-gold deposits.
Noting that VMS districts on average host 12 deposits, cover an 800 square-kilometre area and contain more that 5 million tonnes of contained metal. Ausgold considers Sandfire Resources' recent discovery of ore bodies totalling 0.5 million tonnes of contained copper may not represent district's total mineral resource.
The Company, therefore, completed a high-resolution aeromagnetic survey earlier this year to accurately map the projects sub-surface geology. The aeromagnetic survey was also designed to detect the geophysical signature of any VMS mineralisation that may be present within Ausgold's project area attributed to magnetite within the primary sulphide ore.
A number of discrete magnetic anomalies along the Jenkins Fault and within the Narracoota Volcanics were subsequently identified by Ausgold's aeromagnetic survey.
A shallow air core drilling program was completed over three of these aeromagnetic targets in June. This drilling has provided information on the region's geological setting (including depth of regolith and basement lithology) and is enabling Ausgold to better constrain its geophysical modelling. The Company is presently finalising the modeling of these magnetic anomalies and is planning a reverse circulation (RC) drilling program of these targets in the coming months.
Samples from the recent air core drilling were sent for analysis and Ausgold anticiapates receiving the assay results within the next three weeks.
Earlier in the year, Ausgold completed an airborne electromagnetic (AEM) survey over the Narracoota Volcanic sequence within its Doolgunna Station project. Data from the Company's AEM survey appears to image a pyrrhotitic (iron sulphide) sedimentary unit coincident with the Narracoota Volcanics / Jenkins Fault contact zone. The presence of potential pyrrhotitic unit within Ausgold's project area may mask more subtle electromagnetic responses of any copper-sulphide mineralisation present within this target horizon.
Ausgold is, therefore, undertaking a detailed ground gravity survey over this region of the Narracoota Volcanics in August aimed at directly detecting any VMS ore bodies present within this favourable host rock.
The Company's detailed ground gravity survey will also cover the historic copper-in-soil anomalies over the Narracoota Volcanics sequence within Ausgold's project area. No fewer than three historic copper anomalies have been identified in the southern-most section of Ausgold's Doolgunna Station tenement. During this quarter, therefore, the Company completed a surface geochemical sampling program over these historic copper-in-soil anomalies (and a number of other target areas).
Ausgold anticipates receiving the assays from this geochemical sampling program within two weeks and the Company has scheduled a follow-up drill program of the soil anomalies for the coming months.
In addition to DeGrussa-style copper-gold VMS mineralisation, SRK Consulting has indicated that Ausgold's Doolgunna Station project is prospective for Plutonic-style gold mineralisation. The interpreted greenstone unit in the northwest of the Company's tenement, which represents the Plutonic-style target, has an interpreted strike length of over 10 kilometres and a thickness in excess of 1 kilometre. No previous exploration appears to have been undertaken over this prospective geology. Therefore, during this period, Ausgold completed surface geochemical sampling program over this potential gold target. The Company also intends to drill test a number of geophysical targets within this buried geological unit in the coming months.
The western section of Ausgold's Doolgunna Station project appears to cover the strike extension of Alchemy Resources neighbouring gold deposits. Consequently, during this period Ausgold completed a broad-spaced air core drilling program targeting possible repetitions of this mineralisation.
Samples from this drilling are currently with the lab and the company anticipates receiving the results within the next 3 weeks.