Projects

• Projects Overview
• Gold:
  • Yamarna
  • Central Bore
• Uranium:
  • Thatcher Soak
  • Yamarna Regional
• Other Commodities:
  • Yamarna Nickel
  • Yamarna Chrome / PGE
  • Yamarna Iron

Yamarna Nickel

Recently Eleckra has carried out studies to assess the nickel sulphide and chromite ore potential within the Yamarna greenstones. The initial study indicates that any Ni-Cu sulphide mineralisation within the Yamarna greenstone belt is most likely to be hosted by komatiite ultramafic rocks. Data on the ultramafic rocks within the Yamarna greenstone belt is very limited with most of the useful data located around the chromite mineralisation. Data from geological maps, drill logs, assay data and petrographic descriptions strongly suggest that the ultramafic sequence that hosts the chromite mineralisation at Yamarna South is the basal zone of relatively thin, but laterally extensive (>80km) layered mafic/ultramafic unit probably a sill.

The presence of chromite mineralisation in a strike-limited zone of thickening within the ultramafic zone of the Yamarna sill may be significant. Formation of very chromite-rich cumulates in mafic and ultramafic magmas require exceptional magmatic processes and these are encountered only in very few sills or intrusions. In the Yamarna sill the strike-limited nature of the chromite mineralisation and its presence within a zone of thicker ultramafic rock suggests that magmatic conditions were variable along strike during the formation of the sill formation. This suggests that there were specialised mineralising environments in localised areas (i.e. for formation of chromite and perhaps magmatic sulphides). It is thus probable that zones of thickening within the ultramafic zone of the Yamarna sill may represent loci for formation and/or concentration of any magmatic sulphide present within the sill; i.e. such zones have the highest potential for containing sulphide mineralisation within the sill.

The aeromagnetic maps show that the ultramafic zone changes thickness along strike with the chromite mineralisation occurring in a relatively thick zone. Several other oval magnetic highs have been recognised within the Yamarna Project area that are due or likely to be due to thicker pods of ultramafic rock and that are likely to represent the zones of thickening within the basal ultramafic zone.

Within the area of the Mt Venn Layered Intrusion, two approximately 10km long magnetic features, one associated with copper / nickel bearing pyroxenite and another one with magnetite, have been recognised within Eleckra’s tenements.