The Vast History of Bungonia’s Geology and Mining

Bungonia is a part of the geologically diverse and complex mountain ranges called the Great Dividing Range, which basically runs down the east coast of Australia. The Village sits on the Dalton Fault line and so experiences some usually mild earthquakes.

Mining impacts any community. In the early days of Colonisation the discovery of alluvial gold in the creeks and rives of the Shoalhaven system was an added bonus to the earliest settlers, stockkeepers and others trying to establish a life in a vastly different landscape to the European cities they were used to.

The Aboriginal peoples did not show any interest in, or use for, the gold - unlike Peruvian or other South American groups, so it would seem that conflicts which did arise were mainly over white men stealing Aboriginal women or over their trespass into Aboriginal Lands, rather than for the metals in the ground.

Mining which was of interest to the Aboriginal groups was either for toolmaking useful stone or for clay and ochres for ceremonial uses .Each of these were traded across the continent along the significant trading route networks. Marulan was well recognised as an easy path across the Great Dividing Range so you can well imagine it provided a path for trade among distant communities.

Aboriginal “factory“ sites being explored, recorded and analysed by the Aboriginal groups of Ngunawal, Gundungarra and Wiradjuri in the biggest local mining sites of Boral - Peppertree and Limestone; Holcim and Gunlake - all reveal evidence of a huge “industrial” level production of specialised useful tools and weapons parts over thousands of years.

Because these artifacts can be analysed for their mineral content, age and geological markers, there is now evidence that these items were traded and valued across the continent of Australia.

The early Europeans [from around 1812 illegally living in Bungonia] also exploited the natural stones. Even today businesses are built on the mining of minerals, hard rocks and sands in the Bungonia District.

Bungonia's Geology

Not only does Bungonia have “wet” deposits - limestones and mudstones - encasing plant fossils [“Langinoa” farm, in private hands, has one such area], there are gravel beds and sands, as well as lateritic sheet capping.

It also has igneous intrusions such as the boulder granite spalled on the hills, as at the Jerrara Road and Mountain Ash road intersection, or the granite outcrop beneath the Bungonia Progress Hall in Bungonia Village.

In addition, there is also a volcanic seam connecting that volcanic flow to the Chapman Trig point on Oallen Ford road, where the weathered basalt cap soil is the best agricultural land in the District.

Where the granite flow meets the limestone there occurs the metamorphic marbles which were cut and sent to the Great Hall of Sydney University for flooring and to major churches in this District.

The most extensive and iconic materials affecting the Bungonia geology and landforms are the limestone deposits.

Bungonia was once 12 miles beneath the surface of the primordial seas. As creatures' bones and exoskeletons rained down through the waters, compressing over time, there formed the major band of limestone.

In subsequent millennia this weathered into the most extensive wet cave system on the mainland of Australia -- perhaps even of the Southern Hemisphere. This area is known as Bungonia Slot Canyon, or the Bungonia Gorge. Its most iconic feature is the deepest vertical limestone cliff in the Southern hemisphere.

There is also a lovely watercolour of the Corale, painted by Conrad Martens (1837) in the Art Gallery of WA.  Perhaps bought to fame because bushrangers loved to hide out in the area? 

Caving in Bungonia - an excellent way to learn about the local geology and geography

The Sydney Speleological Society conducts regular caving activities and there are also some highly regarded research books on the caves and their history. 

There are some excellent research papers as well:

A New History of Cave Development at Bungonia NSW by R.A.L. Osborne
Beautiful Bungonia by Joe Sydney

You can source the books below by clicking on the image, although they may be difficult to get. This fabulous review by Dave Gillieson of Under Bungonia may inspire you!

What's Inside...