Nullarbor Plain karst
One of the largest karst areas in the world: some 200,000 km2 of flat limestone across southern Australia, with collapse dolines, blowholes and caves beneath, shallow ones in the Nullarbor Limestone and deep ones 50 to 120 m down in the older Wilson Bluff Limestone.
Dated events and their evidence
- about 40,000,000 years ago mainstream
the Wilson Bluff Limestone, the deepest bedrock of the plain and the host of its deep caves, is laid down in the middle to late Eocene source - about 30,000,000 years ago disputed
one hypothesis: the deep caves form below the water table in the exposed Wilson Bluff Limestone during a warm, wet climate about 35 to 25 million years ago (their origin is still not fully understood) source - about 14,000,000 years ago mainstream
the Nullarbor Limestone, the plain's surface rock, is laid down in the middle Miocene; the plain has since been uplifted and exposed source
Where
30.3000° S, 129.0000° E
Wikipedia's point for the Nullarbor Plain (30°18' S, 129°00' E). The karst covers the whole plain, some 200,000 km2; the photos are from the Caiguna Blowhole and Murrawijinie cave.
Sources
- https://doi.org/10.5194/icg2022-162
- https://en.wikipedia.org/wiki/Nullarbor_Plain
- https://ozgeology.com/blogs/news/a-colossal-cave-system-lurking-beneath-australia-s-desert-the-nullarbor-caves
Each event carries Aion's own evidence grade (mainstream, disputed or speculative). This page repeats what the globe shows for this place.