General Discussion, page-249

So what it boils down to is the Syncline Basin theory is IMHO a Furthy, it's more likely that at some point in geological time subduction along the NW Fault produced some sort of localised effusive volcanic activity and the collapse of the vents produced the Basins that subsequently filled with mud and carbonaceous matter. Evidence of that activity seems to have been eroded away by 200Ma of erosion.



Diapirs are a very prominent feature of the rest of the Flinders Ranges. Volcanic activity is scarce and a lot has been eroded away over 200Ma.




Localised multiple craters are not uncommon.



Hence there are 5 lobes at Leigh Creek and another further to the NW but at depth.