Passages within the Munro Karst caves. (Supplied: South Australian Heritage Council)
In short:
There is a push to add a cave system discovered in a quarry near Naracoorte added to SA's heritage register.
The Munro Karst system was provisionally added to the list last year and efforts are underway to make the recognition permanent.
What's next?
The decision is expected to be made later this year.
A report is being prepared as part of the process to have a cave system that could be two million years old added to the South Australian heritage register.
The Munro Karst system was provisionally added to the heritage list last year following the discovery of the caves in 2022.
The system is located within the Munro Quarry, about 9 kilometres north-east of the Naracoorte Caves, which were added to the World Heritage List 30 years ago because of the megafauna fossils discovered inside them.
A karst is a type of landscape formed when limestone in the ground is dissolved by water and creates features such as sinkholes and caves.
In her previous report nominating the Munro Karst caves for state heritage listing, palaeontologist Liz Reed said the site offered a "rare opportunity to reveal the age and evolution of the area via scientific research".
She said the caves could be about 2 million years old.
The Naracoorte Caves are believed to be more than 1.3 million years old.
Unusual calcified tree roots within the Munro Karst caves. (Supplied: South Australian Heritage Council)
"The caves exposed so far display multiple level passage development, which is rare at Naracoorte and provides insight into the very earliest stages of cave development in the area and a previously undiscovered missing link between these caves and those at the World Heritage Naracoorte Caves," Dr Reed wrote.
During an examination of the caves Dr Reed discovered the tooth of an extinct kangaroo.
Her report said the caves also contained calcified tree roots and associated stalactites, which were unusual for the area.
"The Munro Quarry cave system preserves unique and significant features that represent important geological and palaeontological heritage," Dr Reed wrote.
The palaeontologist said many other caves in the same range of hills could have been destroyed by agricultural practices or during early exploration, while others did not have entrances that made them accessible for people.
The quarry operator has declined to comment for this story.
A model of one of the many skeletons discovered in the Naracoorte Caves. (Supplied: Clay Bryce)
Listing fast-tracked
SA Heritage Council deputy chair Eleanor Walters provisionally added the caves to the state heritage list in August without waiting for the council's next meeting after she received Dr Reed's nomination.
Chair Sandy Verschoor said the move was rare and only used when the site in question was under "imminent threat".
"As well as suggesting that these caves could be among the oldest in the area, if that is actually correct, then this will give us a great understanding about the earliest stages of cave development in the South East,"
Ms Verschoor said.
The caves were listed under the criteria that they "may yield information that will contribute to an understanding of the state's history, including its natural history".
Only one submission was received during consultation about the heritage listing.
"The fact that we've only received one submission and it's in favour bodes quite well for the work we're going to do," Ms Verschoor said.
A state heritage listing restricts what development can be done to a site but also highlights its value to the public.
A decision on a permanent listing is expected to be made by the middle of the year.
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