To date, five zones of mineralisation have been identified along the shear within Norwest’s Bali project area. These zones of mineralisation have only been lightly drill tested to date with the majority of holes testing only the top 30 metres. Positive results from the historic drilling include:
- 9 metres @ 2.14% Copper & 9.8 g/t silver (Drill hole CL4)
- 3 metres @ 3.75% Copper & 18.3 g/t silver from 5 metres downhole (Drill hole CL1A)
- 6 metres @ 7.17% Copper & 27.3 g/t silver from 17 metres downhole (Drill hole CL1A).
The airborne electromagnetic (AEM) and magnetic survey was conducted across the entire Bali Project tenement area and came less than a month after the Company’s successful listing on the ASX.
The AEM and magnetic data was collected using the latest Xcite airborne system, developed by New Resolution Geophysics Australia’s (NRG). The specifications of this survey included a line spacing of 100 metres, flown on a north-south grid pattern to maximise resolution of any primary base metal mineralisation that may be present with the shear system. Based on these specifications, NRG indicate that the Xcite system could detect copper mineralisation at the Bali Project from surface to a depth of at least 300 metres.
The survey data was processed and assessed by Perth based Southern Geoscience Consultants.
The high-resolution airborne electromagnetic (AEM) and magnetic survey totalled 441 line-kilometres which covered the entire Bali Project. The survey was designed to highlight conductors representing potential primary copper mineralisation that may be present within the project area.
Processing of the data to date, does not reveal strong, discrete EM anomalies that present as walk-up drill targets. Strike-extensive structures that host the known copper mineralisation are evident in both the EM (as an IP effect) and magnetic datasets. Overall, however the Bali mineralisation doesn’t have a conductive AEM response. Drill targeting will be driven by the known geology and drilling at this stage, with the geophysics to map out the host structures.
Future exploration work is recommended to include:
- a structural and lithological interpretation of the magnetic and EM data to build a project-wide framework to develop a set of targets based on integrating the interpretation results with all available geological data.
- Characterise the physical properties of the known mineralisation to more accurately assess what geophysical methods may directly detect mineralisation. Ideally this is done on fresh drill core and hand samples if suitable.
- Ground geophysical surveys which will require careful considered given the difficult access and terrain.
- Test Down Hole EM could be carried out if drilling proceeds, to assess potential mineralization in closer proximity.