I saw the abstract of this about 6 months ago via a mate, who shared the pre-publication peer review edition. The other one of note is a report on Abra, which also shows multiple episodes of hydrothermal activity in the Bangemalls.
As I said elsewhere, the paper definitively associated DeGrussa as a Besshi type VHMS, ie, mafic-siliciclastic.
The geochonology also shows there are multiple mafic volcanic events, but only the one associated with DeGrussa is of interest; not the earlier one sandwiched inside the johnson Cairn Fm, and not later dolerite dykes.
These three mafic lithologies have different geochemical signatures which can be investigated by whole rock and trace element geochmistry; you can determine if your mafics match the Boninite affinity, and could (if you wished to spend the money) run the zircon ages (or similar) and ping a date on your package of mafics and see if it is in the sweet spot age wise.
There are also some other brutal home truths for various companies and investors.
firstly, Sipa's ground at Enigma is ~500Ma too young. it cannot, logically, be a VHMS and is some later sedex / sediment replacement or even MVT hybrid mineralisation. Enigma is way too far up-section in the Yerrida to be anywhere near cooee of a VHMS. So, IMO, if you're in for a DeGrussa play on AUZ, LSR, etc, you're deluded. Flog out and buy the right ground. The further east of the Goodin Fault you get, the less likely a Besshi becomes because the mafics in that basin are arc-continent and continental affinity mafics of the wrong age.
secondly, a lot of ground is held in the upper portions of the narracoota and in all-mafic volcanic areas. Like, the middle of the basin. or the upper contact with the Horseshoe iron Fm. This is all moose pasture, barring some luck. besshi's in maficmafic positions tend to be small. I'm looking mostly at the RNI ground near Cashmans, seems too far back from the arc position along the north of the basin and too thick with peridotitic and mafic-mafic contacts.
thirdly, anything in the Doolgunna Fm (like a few of ENT's conductors)? dogs. Wouldn't drill them.
Fourthly, other 2050-1980 rocks do exist, eg, Camel Hills. However, barring some new data, it looks to be off the arc position and seems to be an immature reclosed continental back arc. No VHMS hope there at all. Don't get deluded.
Finally! The jury is also still well and truly out on Peak Hill - 5-ways and Fortnum (Grosvenor) insofar as timing goes. There's association in the metamorphic (not mineralisation!) ages between Peak Hill and camel Hills, so it looks prospective for lode gold....but...there's another 3 or 4 possible, later culprits to place Fortnum into, let alone Harmony-Enigma Au, Horseshoe-Cassidy etc. The Au story is far from resolved (it's a VHMS timing data, mostly, and recalcuating data with a different lead decay model).
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