Australian exploration company Estrella Resources Limited (ASX: ESR) has provided an exploration update for its Carr Boyd Nickel Project, located approximately 80km north north-east of Kalgoorlie Western Australia, identifying two significant conductors close to existing high priority exploration targets.
The company recently completed a Phase II moving loop High Powered Electro-Magnetics (HPEM) survey, which was proposing to extend 3.3km further north from the Phase I survey completed earlier this year. It screened the interpreted basal contact position and immediate footwall sequence to 1.4km north of the Carr Boyd Rocks Mine.
There are several historic high priority exploration targets and prospects in this area based on surface geochemistry, down hole geochemistry, aero-magnetics, ground gravity, and interpreted geology data sets. The Phase II HPEM has now defined two significant conductor’s,Target A and Target 5, indicative of the presence of well-developed sulphides associated with two of the exploration targets.
The first known report of this target appears in an internal company report written for Titan Resources in 2004. It is described again in an internal company report written for Yilgarn Mining in 2008.
The target is defined by a 450m long zone of highly anomalous nickel and copper mineralisation in drilling, located approximately 100m south of the newly defined EM conductor. The mineralisation and EM conductor appear to be located on or very close to the interpreted basal contact position of the Carr Boyd Nickel Project. Historic drilling does not appear to have tested the conductor defined by the recently completed Phase II HPEM.
The EM conductor is discrete and moderately to highly conductive. The modelled conductance is 3000 – 5000S, and according to Estrella makes this a very high priority drill target.
Historic drilling returned many anomalous results over a 450m strike length of the interpreted basal contact at Target 5. The best of which was 3.35m at 0.79% Ni and 0.35% Cu, including 0.61m at 2.12% Ni and 0.56% Cu from 100.89m in GD124. This occurs in a zone of disseminated and matrix sulphide on the interpreted basal contact of the Carr Boyd Nickel Project. This is very positive support for the EM conductor located approximately 300m along strike to the north.
According to Estrella this is a conceptual satellite style target located on an interpreted fault outside of the Carr Boyd Nickel Project in the footwall sequence. The target area also appears in the Titan and Yilgarn Mining reports, although the newly defined EM conductor is located approximately 200m further west, on a different magnetic feature.
A diamond drill hole spudded by Defiance Mining in 1997, DD97CB043 appears to target the conductor position, suggesting it was detected by a SiroTEM survey completed at that time. Interrogation of the available data sets suggests the hole did not intersect the conductor, although more investigation is required to confirm this.
Estrella aims to locate the hole collar in the field and have it picked up by a licensed surveyor. If the hole can be re-entered and gyro surveyed that will also be completed. As geological logs are not available for the hole, the core will be re logged and physical property tests carried out on it to determine the best course of action for the EM target.
The Carr Boyd Nickel Project is a 75km2 layered mafic igneous complex, which hosts several occurrences of nickel and copper sulphides. The most significant occurrence discovered to date is at the Carr Boyd Rocks mine, where mineralisation is hosted by bronzitite breccias (pyroxenites) emplaced within the gabbroic sequence of the Complex. The Carr Boyd Nickel Project is in a Tier 1 jurisdiction approximately 80km north north-east of Kalgoorlie Western Australia. An all-weather haul road accessible by Estrella under a granted miscellaneous license connects the Project to the Goldfields Highway via Scotia.
A “Voisey Bay” style model has not been adequately explored within the Carr Boyd Nickel Project This represents a compelling exploration target opportunity which the Company will continue to aggressively pursue.