Really interesting, hearing that the volcanic plume is now believed to be off north-west Tasmania! It'd be amazing if we saw a new volcano forming there, like Surtsey in Iceland in 1973!
I remember when we first lived in Melbourne we were standing on the top floor of a car park one day, and as I was waiting for my husband to open the car, I looked around to see the hills in all directions. I realised that I was standing in a Caldera. I went home and checked online, and it is!
So it's under an interesting piece of geology right now. Tasmania being a remnant of the Antarctic plate. It seems as though it started out more powerful or closer to the surface given the size of the Mt Warning Caldera do we know what it's up to now. Did the ongoing collision with Zealandia push it down. Given it's trajectory, will we some day see it resurface??
If the cosgrove hotspot has moved from Queensland all the way down to Vic/SA ... and the last eruption being Mt Gambier 5,000 years ago. What has caused the last Queensland eruption only 13,000 years ago? 🤔 Surely it couldn't have moved down to Vic/SA within 8,000 years? Not that quickly.
They are all different things that aren't directly related to one another. The Mount Gambier volcano is part of the Newer Volcanics Province which stretches from Melbourne to Mount Gambier, and is not the result of the Cosgrove Hotspot. The Cosgrove Hotspot never touched South Australia, however it was responsible for Hanging Rock in Victoria which is currently within the Newer Volcanics Province, but Hanging Rock dates to around 6.5 million years ago, predating the present ongoing volcanic activity of the area by a couple of million years. The recent volcanism of northern Queensland is also not related to the Cosgrove Hotspot, but is thought to be due to either a single large magmatic plume affecting an enormous area throughout the Einasleigh Highlands and surrounds including the Atherton Tableland or possibly several separate magmatic plumes. Personally though, I think Australia has awoken from its geologic slumber, and the recent volcanism of northern Queensland, southern SA/central and western Victoria, the recent uplift and tectonic reactivation of the Flinders/Mt Lofty/Barrier Ranges, the subsidence of Lake Eyre/Kathi-Thanda and surrounding playas, the very rapid creation of the Otway and Strezlecki Ranges, the widespread uplift of the Great Dividing Range and associated tablelands with their telltale incised meanders indicating very recent topological change from a depositional environment to an erosional environment due to rapid but uniform crustal uplift, the creation of Lake Bulloo due to the recent damming of the Bulloo River, the associated creation of the large wetlands in southwest Queensland due to the almost damming of the other Channel Country rivers, the renewed tectonic activity of the Central Ranges with again telltale incised meanders very widespread and conspicuous, the northwest tectonic zone, all of that and I'm sure plenty more that I've forgotten or aren't aware of, likely being related to the ongoing collision of Australia-New Guinea with the Volcanic Island Arcs of Wallacea and the South Pacific... which is also the current leading theory as to the cause of the formation of the Rocky Mountains in North America which push far further into the interior of the continent than a standard ocean crust subduction under continental crust would normally form (the classic textbook example of that being the Andes of South America). Take everything I just said with a grain of salt though, as I have zero geological training and I'm just an uneducated pleb with a minor interest in the subject and a kink for staring at maps for hours on end.
