One of the most unique geologic settings in Australia lies in the Kimberly Region of northern Western Australia. While most of us know Western Australia for its mineral resources, the region also contains exceptional paleontological resources. The Great Devonian Reef is one of the most impressive of these resources.
The Devonian reef is preserved in incredible detail, waiting to be discovered by the intrepid explorer. This little known paleontological treasure has drawn researchers and visitors from around the world.
Before we go into the details of visiting, let’s learn some more about the geology of the region:
In the Devonian, about 350 million years ago, a shallow sea extended deep into the Canning Basin, the product of a failed rifting event. Near the edge of the sea was a series of shelves where the water was shallow. Some of the shelves contained islands, which were made up of resistant quartzites.
The swiftly moving shallow water near the north shore of the basin was the perfect environment for stromatoporoids, armored sponges which survive by filtering nutrients from the water. Like corals, stromatoporoids are capable of building massive reef structures
The stromatoporoid reef grew and thrived for millions of years. Eventually, however, sea level rose and the reef was buried by thick layers of sediments.
For hundreds of millions of years nothing happened. That may not seem too exciting, but it was the almost total lack of tectonic activity in Western Australia that allowed the reef to be preserved in such good condition. It’s only in the past few million years that erosion has finally removed the overlying sediments, exposing the reef and the quartzite islands associated with it.
Visitors today will find a geologic wonderland. Boab trees grow out of crevices in ancient reef structures containing countless fossils. It’s impossible to walk around without crunching fossils underfoot. In the best preserved spots, it’s possible to observe the different parts of the reef, including unique near-shore fossil ecosystems, in three dimensions. It’s almost as if someone drained all the water away from the modern Great Barrier Reef, allowing people to explore it on dry land.
The hardest part about visiting the Devonian Reefs of the Kimberly is getting to them. The best places to access the reef are at Windjana Gorge National Park, Geikie Gorge National Park, and Devonian Reef Conservation Park. All of these parks are located in a cluster about 400 km west of Broome, and almost all (except for Geikie Gorge) are best reached with a four wheel drive vehicle.
Despite the remoteness of the location, paleontology enthusiasts and geologists will find the visit well worth their while.
To learn more about the Devonian reefs, check out the links below.
Visiting the Devonian Reefs:
Detailed academic reports: