I've been doing a bit of research on gold mineralised salt lakes and although KWR use the analogue as Kanowna Belle, there are quite a few similarities with the Invincible deposit at St Ives discovered under Lake Lefroy as recently as 2012.
They have the same Black Flag formation as we do on Lake Goongarrie.
Currently owned by Goldfields but originally owned by WMC.
When they took over they went over some old drilling results that were never properly followed up on.
Below is an excerpt from the presentation 2014.
ST IVES INVINCIBLE DISCOVERY UNDER LAKE LEFROY.
https://www.goldfields.com/pdf/investors/presentation/2014/diggers-and-dealers/presentation.pdfGOLDFIELDS PRESENTATION DIGGERS AND DEALERS 2014
An Air Core programme was initiated in 2011 which identified an anomaly warranting further follow up. We then planned a diamond drill programme targeting the structure which was completed in 2012. The location of the diamond holes can be seen here in yellow. The results were better than could be expected, with ore intersected in 4 holes over a 1km strike length and the best being 12m @ 5.5g/t from 25m. The remaining 3 holes were,
14m @ 3.9g/t from 26m,
3m @ 5.0g/t from 73m,
6m @ 2.3g/t from 46m.
This was immediately recognised as a significant discovery and was the starting point for the resource we have today.
Mineralisation is hosted within a unit called the black flags mudstone which varies in thickness from 15-100m
..............................................................................................................................................................................From the KWR discovery announcement Sept 13.Results include 3m @ 6.5 g/t Au and 3m @ 4.1 g/t AuThis mineralisation corresponds to a NW-trending zone of D4 cross-faulting where this intersects and displaces a thick Black Flag Group conglomerate unit.
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For those that want to know what a D4 fault is,
D4 Faults. (a regional-scale brittle-ductile fault network (D4))
D4 faults are where you are going to find gold.
https://espace.curtin.edu.au/handle/20.500.11937/169
Abstract
Late-Archaean deformation at Ora Banda 69km northwest of Kalgoorlie, Western Australia, resulted in upright folds (D2), ductile shear zones (D3), and a
regional-scale brittle-ductile fault network (D4).
Early low-angle faults (D', D1), documented in the surrounding Coolgardie, Kambalda and Boorara Domains are not developed in the Ora Banda Domain, and the fabrics reflect only the latest ENE-WSW shortening event. The western limb of the regional-scale ESE- plunging Kurrawang syncline (D2), is truncated by the Zuleika Shear Zone (D3), a within- greenstone ductile shear zone located 10km southeast of Ora Banda. The shear zone has a much greater strike length (250km) than depth extent, as seismic imagery reveals a sharp truncation against a mid-crustal decollement at a depth of 6km-depth below surface.
The Zuleika Shear Zone is a NW-SE trending band of anastomosing S-C mylonite zones formed in conjugate sets of NW- SE trending sinistral and N-S trending dextral shear zones. Widely distributed flattening strains and more restricted zones of non-coaxial shear in the Zuleika Shear Zone, suggest deformation-path partitioning typical of a transpressional tectonic environment.
Latetectonic brittle-ductile faults (D4) cross-cut the Zuleika Shear Zone and surrounding greenstones, and hence are not Riedel structures or other lower order faults genetically related to the ductile shearing.
Gold mineralisation of the Zuleika Shear Zone began during the ductile deformation (D3), continued through peak metamorphism that postdates the shearing, and finally ceased after the brittle-ductile faulting event (D4). Gold deposits are primarily located where brittle-ductile faults intersect the Zuleika Shear Zone. Brittle-ductile faults (D4), are developed in three principal structural orientations: N-S (dextral), NE-SW (dextral) and E-W (sinistral). These faults display mutual cross-cutting relationships and were formed synchronously during a single regional shortening event. The brittle-ductile fault network is developed unevenly over the region, being localised in packets of high fracture-density referred to as structural zones. The Ora Banda structural zone is an area of high density faulting in the vicinity of Ora Banda, composed of a network of interlinked faults in which alternating ductile and brittle conditions produced cataclasite, breccia and quartz vein systems overprinting mylonite and schistosity. Other areas of high fracture-density (eg. Grants Patch and Mount Pleasant structural zones), are located within the NW-SE trending Ora Banda mafic sequence and spaced at 10km intervals to the southeast of Ora Banda. This spatial periodicity of high fracturedensity within the mafic sequence may have developed as a result of layer-parallel extension during ENE- WSW regional shortening. Gold deposits are concentrated in the Ora Banda, Grants Patch and Mount Pleasant structural zones.
Gold distribution within the Ora Banda structural zone traces out the distribution of brittle-ductile faults, indicating that the fault network was the major pathway for fluid flow during mineralisation. Hydrothermal minerals are integral components of fault fabrics within the structural zone, and textures indicate that the faults were formed under conditions of high fluid pressure and, for much of the deformation, may have been fluid-generated. At Ora Banda the Enterprise gold deposit (40 tonnes Au) highlights the control of mesoscopic- scale fractures on gold distribution.
https://www.sciencedirect.com/science/article/pii/S1674987118300409Most authors place these fault arrays as D3 to D4 in a D1-D4 structural sequence (e.g., for Kalgoorlie: Vielreicher et al., 2016: table 2) and consider them as post-gold structures (e.g, for Kalgoorlie: Boulter et al., 1987, Mueller et al., 1988, Bateman and Hagemann, 2004, Gauthier et al., 2004, Weinberg et al., 2006). However, there are a number of lines of evidence suggesting that these ubiquitous structures are the major structural controls on the location of gold mineralization. For example, gold mineralization may be hosted in earlier structures but may be totally confined between a pair of the oblique faults. Again, using Kalgoorlie as an example, the Mt Charlotte deposit is confined by two subparallel D3/D4 faults and the various lodes in the Golden Mile are hosted by D2 structures but the mineralization in the Golden Mile superpit is essentially confined between two D3/D4 faults: the Adelaide and Golden Pike Faults (Fig. 4). As shown by Vielreicher et al., 2010, Vielreicher et al., 2016 all gold deposits are essentially the same age as these faults. The gold deposits at Kundana (Cooke et al., 2017) lie on a jog in the Zuleika Shear Zone, a crustal-scale fault that lies to the west of the Boulder-Lefroy Fault. As for the Boulder-Lefroy Fault at Kalgoorlie, the Zuleika Shear Zone jogs from its normally north-northwest trend to a roughly northwest trend with an array of broadly NE-trending cross faults coincident with this jog. The orogenic gold deposits are confined to this jog and are sited in a number of D2 shear zones at, or close to, their intersection with the cross-fault arrays (Fig. 5). Importantly, the lodes may be located on one side of a cross fault, but not consistently displaced to the other side of the fault.
