The Carrapateena alteration and mineralization system is buried beneath ~500 metres of cover rocks. If it were near surface, say in the top 200 metres, the gravity anomaly would have a magnitude more than double what it is.
The modelled densities at the Pokali prospect (max. 2.8 gcm-3 according to the map) are not high enough to represent significant amounts of hematite alteration, which is characteristic of IOCG deposits in SA's Gawler craton.
In addition, the best mineralisation to date is associated with magnetite and biotite alteration. This means it formed relatively deep and hot, compared to Olympic Dam, Prominent Hill, Oak Dam West or Carrapateena. It doesn't look anything like a South Australian IOCG. It has more similarities with the systems from Cloncurry, albeit seemingly without common features such as red-rock and calcsilicate alteration (from low res photos).
As for other anomalies, I think the Avalon target looks interesting. At least they have modelled densities >3 gcm-3 at that target. It would be nice to see it a bit higher again, but its getting around the mark. The disclaimer here is that there is an infinite number of solutions to these potential field geophysical models...
The negative is I haven't seen any geological context for Avalon, nor any associated magnetics (I must admit, I haven't looked very hard for that info). There is a risk that the anomaly is sourced from barren mafic rocks. If you look at historical IOCG exploration in SA there were dozens of targets drilled that turned out to be only dense, mafic rocks.
One could screen the targets with induced polarization (IP) surveys, as a large body of iron oxide should give a whopping chargeability response. Of course, this adds some pre-drilling cost, but assuming the surveys had the depth penetration it could sterilize some of your targets and provide additional focus.
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