The Kudz Ze Kayah (KZK) project is wholly owned by BMC Minerals, a subsidiary of BMC (UK) Limited. BMC Minerals holds 100% of the rights to the project.
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Summary:
The Kudz Ze Kayah Project area, comprising the Kudz Ze Kayah claim blocks within which the ABM deposit is located, encompasses units of the Grass Lakes group.
Deposit Geology
The ABM deposit (comprising the ABM Zone and Krakatoa Zone) primarily comprises continuous, shallowdipping massive sulphide mineralization hosted within a thick felsic package of volcaniclastics and coherent sill/flow complex that locally make up the Kudz Ze Kayah formation.
Massive sulphide of the ABM Zone is hosted within a felsic rock package, whereas the Krakatoa Zone is predominantly hosted by a pre-mineralization mafic sill located within the felsic volcanic package. Mineralization at Krakatoa also occurs in the felsic hangingwall units stratigraphically overlying the mafic sill, in what is broadly interpreted to be the equivalent of the ABM mineralized position. Only scattered vein-style and disseminated mineralization occurs within the mafic sill lying stratigraphically below the ABM Zone.
The upper limits of the ABM and Krakatoa Zones are truncated near surface and overlain by glaciofluvial sediments ranging in thickness from approximately 2–30 m.
A post-mineralisation brittle fault zone (East Fault) offsets the ABM and Krakatoa Zones, and angular clasts of sulfide are to be found within the fault zone breccias. The south-eastern margin of Krakatoa is cut by another late brittle fault zone of the same generation (Fault Creek Fault). There exists a marked difference in the stratigraphy east of the Fault Creek Fault, with recent drilling having identified a package to the east of the fault, dominated by stratified felsic volcaniclastics and minor felsic intrusives, which transitions conformably up into the overlying Wind Lake formation. The marked change in volcanic stratigraphy across the Fault Creek Fault, despite little or no evidence of a significant offset of the Wind Lake formation basal contact, potentially indicates the presence of a syngenetic fault structure along the south-eastern limit of the Krakatoa Zone. Similarly, attempts to reconstruct the ABM Zone and Krakatoa Zone into a single massive sulfide unit are not consistent with the degree of movement observed along the East Fault when using the Wind Lake formation basal contact as a reference. These features indicate the likely presence of syngenetic fault structures either side of the Krakatoa Zone that was later the locus for late-stage brittle faulting.
Mineralization
ABM Zone
The massive sulfide of the ABM Zone is up to 39 m in true thickness, extending approximately 700 m along strike and approximately 500 m down dip. It dips to the north-northeast at approximately 35° near surface, transitioning to a dip of approximately 15° at around 200 m depth below the valley floor. The up-dip extent of the deposit is truncated by erosion and covered by approximately 2–20 m of glaciofluvial overburden and the down-dip margin of the ABM Zone appears to transition into a mixed and variably carbonaceous felsic volcano-sedimentary package.
Massive sulfide mineralisation occurs as several stacked massive sulfide lenses to the west, transitioning to a single massive horizon at around 415,025 mE and extending to approximately 415,250 mE, where it is then truncated by the East Fault.
Stockwork and disseminated mineralisation are present equally – in the hanging wall and footwall – to massive sulfides and are also present to a lesser degree between the massive sulfide lenses.
The sulfide mineralisation is dominated by pyrite, sphalerite, pyrrhotite (±marcasite), galena and chalcopyrite, with minor arsenopyrite and a range of sulfosalts predominantly comprising tennantitetetrahedrite and freibergite. The up-dip part of the ABM Zone and most of the Krakatoa Zone have elevated sulfosalt content relative to the remainder of the deposit.
Krakatoa Zone
Mineralisation at Krakatoa is broadly concordant with the stratigraphic layering of the host Kudz Ze Kayah Formation rocks and dips at 35° to the north-northeast extends over approximately 200 m of strike, at least 500 m down dip, and up dip to the base of glacial overburden which is approximately 30m thick. Mineralisation is bound to the west by the East Fault, to the east by the Fault Creek Fault and currently remains open at depth beyond the down-dip extent of the mafic sill.
The distribution of mineralisation within the Krakatoa Zone is more spatially complex than the ABM Zone as it is a stacked lens system with massive sulfide mineralisation occurring within three principal mineralised horizons:
• Upper Lens – broadly interpreted as the stratigraphic equivalent to the ABM Zone.
• Main Lens – the major component of the Krakatoa Zone with a true thickness of up to 22 m.
• Lower Lens – less pronounced and semi-continuous.
Host rock types and alteration styles associated with Krakatoa Zone mineralisation are similar to those encountered in the ABM Zone. The key difference is the degree of mineralisation associated with the mafic sill, which below the ABM Zone is only poorly mineralised. The Main lens comprises the bulk of mineralization at Krakatoa, with massive sulfide occurring both within the felsic volcanics immediately beneath the mafic sill, and within the mafic sill, after replacement of enclaves of felsic volcaniclastics and/or replacement of the mafic sill itself.