Wodger, Big Billy and Forrest have been linked to Horseshoe Lights by the company's geologists based on;
- the contact between the Narracoota and Ravelstone Fm being present within or near all occurrences
- the copper content
- an assumption that these similarities are caused by, and causative of, VH(M)S mineralisation (note the lack of massive in the sulphide)
Be-Te-Bi-W-Au is, in many situations, equally an association of felsic igneous rocks, many of which do not carry any base metals (eg; distal to deep-seated plutons and volcanism). Given the Callies-Trevs stratigraphy at Fortnum is felsic welded tuff breccia, also within the vague stratigraphic position of the NV/RvFm contact, it is not perhaps diagnostic of VH(M)S and more diagnostic of felsic volcanism in the seafloor environment at the chronostratigraphic interval. ie; the felsics provide the Be-Te-Bi-W etc etc.
Given the contact has been reactivated by/as a thrust at Callies and at Trevs, for epigenetic Au, there is a non-genetic and non-causative association between felsic suite elements and Au.
GLN and Homestake and Harmony and others explored this prospective contact for Au only. The copper was found at Big Billy by accident (and spotted because it's in the RvFm turbidites). GLN missed the oxide copper at Forrest Gimp / Wodger in their AC drilling a decade ago. None of them explored for Cu or Be-Te-Bi-blah blah.
So, firstly, don't conflate Au only exploration as exploration supportive of this company's theories.
Secondly, don't take onboard a theory and a metal association without critically assessing whether there are other plausible explanations. it's unusual to see two mineral systems in the same place, but it's known (eg; Mt isa, and Abra espeically). So, thrust-related Au-plus felsic alphabet tracers in an epigenetic system, and then a later low-sulfidation bornite wash coming in the structurally prepared fractures which the Au exploited. Plausible - and just as plausible as VH(M)S given a lack of massive sulphide under the best and deepest and strongest part of the anomaly and a preponderance of epigenetic textures.
I'm interested to see how they go. a 100m pre-strip of very low grade oxide to get low-moderate grade Thaduna style mins is maybe not a supermodel, but it's no 2 a.m. barfly either
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