Chalice identifies major new 6.5km-long EM anomaly at Julimar

by Leena Thomas
Image: Chalice Gold Mines Limited

Chalice Gold Mines Limited (ASX: CHN | OTCQB: CGMLF) announced that the preliminary results from the airborne electromagnetic (AEM) survey has revealed three new large EM anomalies (Hartog, Baudin, and Jansz) at the company’s Julimar Ni-Cu-PGE Project in Western Australia.

The company reported that the new Hartog EM Anomaly extends ~6.5km beyond the northern limit of drilling at the ~1.6km x 0.8km Gonneville Intrusion, where Chalice made a significant greenfield PGE-Ni-Cu-Co discovery in March.

CHN said that the results highlight the district-scale Ni-Cu-PGE potential of the ~26km long Julimar Complex.

Chalice said that four rigs continue the resource drill-out at Gonneville, with assay results pending for 50 holes. The company said that it is fully-funded with ~$46 million in cash as of 30 June 2020.

Julimar project

The Julimar Nickel-Copper-PGE project is located 70km north-east of Perth in Western Australia. The 100%-owned Julimar Project covers the entire >26km long Julimar Intrusive Complex (~26km x ~7km mafic-ultramafic layered complex) and ~24km of the highly prospective complex is yet to be explored.

Chalice commenced a systematic, greenfield exploration program in mid-2019 in the southern portion of the Project, on private land, targeting high-grade Ni-Cu-PGEs.

An initial RC drill program commenced in Q1 2020 and resulted in the discovery of high-grade nickel-copper-cobalt-PGE mineralisation at the newly named Gonneville Intrusion.

Airborne EM survey at Julimar

The company said that a helicopter-borne low frequency electro-magnetic (EM) survey was recently flown across the entirety of Chalice’s granted tenure on 200m line spacing at the Julimar Project. The survey was designed to test for conductors within and proximal to the Julimar State Forest.

CHN said that by also flying over Gonneville, the survey was able to calibrate against the known high-grade PGE-Ni-Cu-Co sulphide zones identified from ongoing drilling. The Gonneville G1 Zone hosts some of the highest-grade mineralisation within the Gonneville Intrusion and was successfully detected in the AEM survey.

Three EM anomalies outlined

The company announced that the survey has outlined three new extensive EM anomalies within the Julimar State Forest – Hartog, Baudin, and Jansz.

Hartog EM Anomaly

The company said that the Hartog EM Anomaly extends for ~6.5km directly north and along strike from Gonneville, and is the highest priority target.

CHN said that the anomaly appears to be offset to the west of the magnetic response of the interpreted Julimar Complex. The company said that the most likely explanation for this is that, given its location directly along strike of Gonneville, it is potentially a less magnetic extension of the mafic-ultramafic Gonneville Intrusion.

The company said that the lack of outcrop in this region precludes a definitive geological interpretation, however non-magnetic mafic rock-types (gabbro) have been identified in drilling at Gonneville and therefore may occur elsewhere in the district. CHN said that this suggests that less magnetic areas within the Complex may also be highly prospective – also a positive indication for EM Conductor X, currently being tested by diamond drilling immediately north-west of Gonneville.

The company said that the peak AEM response of the Hartog anomaly is significantly stronger than the peak AEM response at the high-grade G1 Zone at Gonneville, indicating a potentially shallow, large conductive body that may represent sulphide mineralisation.

Baudin EM Anomaly

CHN said that the Baudin EM Anomaly is located proximal to a discordant feature in the magnetic signature of the Julimar Complex, approximately 10km north-east of Gonneville within the State Forest. This area was previously sampled, with strongly anomalous Ni-Cu-Pd in soils identified in the area.

Jansz EM Anomaly

The company said that the Jansz EM Anomaly is located approximately 18km north-east of Gonneville, partly within State Forest and partly on private land.

Further modelling and ground EM

The company said that the Baudin and Jansz anomalies are discernible in the early to mid-time channels only, potentially indicating surficial responses, however further modelling and ground EM is required to confirm the prospectivity of these targets.

CHN said that the final geophysical survey data is yet to be received and it is possible that additional anomalies may be identified. The company reported that the final modelled anomalies will be followed up with ground-based geophysics in order to define drill targets, upon access being granted to the Julimar State Forest.

What’s next?

The Company announced that it has been actively liaising with the Department of Biodiversity, Conservation and Attractions (DBCA) and the Department of Mines, Industry, Resources and Safety (DMIRS) regarding the development of a Conservation Management Plan (CMP) for non-ground disturbing, reconnaissance exploration activities within the Julimar State Forest.

Proposed activities include ground-based geophysics as well as wide-spaced geochemical soil sampling over the entire Julimar Complex, including the three new AEM anomalies. These activities are anticipated to have negligible impact on the environment and community.

The company said that any targets generated from these activities would be drill tested, subject to a second stage CMP approval.

Chalice reported that it will continue to work co-operatively with regulatory agencies regarding environmental approvals for future exploration.

The company said that a resource drill-out is ongoing utilising 4 drill rigs over the Gonneville Intrusion

Management comments

Chalice’s Managing Director, Alex Dorsch, said: “We have speculated for some time that the area north of our recent Gonneville discovery is highly prospective. We have now supported that claim with major new, laterally extensive geophysical targets from the first airborne EM survey over the Company’s granted tenure, which is a very exciting and important development.

Airborne EM is an effective first-pass screening technique that can detect shallow conductive sources, such as nickel sulphide mineralisation. It is important to emphasise though that our experience at Gonneville to date has shown that some high-grade mineralised zones do not necessarily have a strong EM response using either airborne or ground-based techniques. Therefore, the absence of a strong late-time airborne EM response does not preclude the presence of mineralisation elsewhere within the Julimar Complex.

We are expecting initial feedback shortly regarding access to the State Forest for the next stage of reconnaissance exploration activities. We are hopeful of being able to assess the compelling new anomalies and aim to expand Julimar into a district-scale, multi-discovery opportunity.

Meanwhile, our resource drill-out is continuing at Gonneville, with four rigs currently drilling and numerous assay results pending.”