Despite highly prospective stratigraphy of the Eastern Succession continuing south under cover, the region is vastly underexplored.  Critically, there has been very little drilling where cover exceeds 300 m. SXG's Isa project, where cover is between an estimated 250 and 400 m, leverages geophysics and pursues the opportunity for discovery of large iron oxide copper gold (IOCG) and Broken Hill-type (Cannington-style) deposits.

Work to date has included collection of new airborne magnetic data (50 m spacing) and ground gravity data (1 km spacing) across the project area.  These surveys were co-funded by a Queensland Government Collaborative Exploration Incentive (CEI) in 2019 ($100,000 grant).  In collaboration with industry-leading geophysicists and structural consultants, these data enabled refinement of existing targets and identification of new targets.

A focus of these efforts has been the F11 gravity target.  This is a coherent, multi-point1.95 mgal residual gravity anomaly with an adjacent magnetic high.  3D inversion modelling of the newly collected magnetic and gravity data supported precise drill targeting.  A second successful CEI grant ($200,000) co-funded drilling of the F11 target in 2020. Final hole depth was 849.7 m.

Encouragingly, disseminated and veinlet-style pyrrhotite-chalcopyrite was intersected over a broad interval in the lower part of the hole (from 750 to 839 m).  Multi-element assays highlight anomalous copper (20 m at 730 ppm Cu and up to 0.87% Cu in selected samples), along with elevated silver, zinc and arsenic.  This elemental association may indicate the outer alteration halo of an IOCG mineral system.

Two high priority gravity targets within a major structural corridor remain undrilled (EPM 26481).  New gravity and magnetic data is yet to be collected over the more recently granted EPM 27626.

SXG continues to evaluate the Mount Isa project and consider further geophysical surveys to assist drillhole targeting.

Location of the Mount Isa project.  Also shown are selected mines highlighting it has been more than three decades since the last major economic discovery in the region.

Compilation of historical drilling within and adjacent to SXG tenure.  Following the discovery of Cannington in 1990, drilling progressed southeast under cover, but effectively stopped where cover exceeds 300 m thickness. Also shown is the location of SXG (Mawson Qld) drilling at the F11 gravity target.

Airborne magnetics and ground gravity showing the increased resolution of data collected by SXG (Mawson Qld), and derived gravity-structural-stratigraphic targets.