Mysteries of the Lost City

One forms low stony ridges while the other has weathered to form interesting sandstone pillars known as ‘Lost City’ formations.
One forms low stony ridges while the other has weathered to form interesting sandstone pillars known as ‘Lost City’ formations.

Caranbirini Conservation Reserve is near Booroloola. At only 1200 hectares it is one of the smaller reserves in the NT.

Unlike many other remote parks it is easy to get to because its short gravel access track leads straight off the bitumen of the Carpentaria Highway.

The park is accessible to 2WD vehicles year round.

You may not be able to camp at Caranbirini but there is a walking track there that is equal to any of the best short hikes in Australia.

The 2km Barrawulla Loop Track crosses the Caranbirini Waterhole before winding through towering the sandstone pillars that are such a feature of the Gulf country.

Sandstone is made up of sand-sized grains of rock fragments and individual minerals broken down from other, older rocks.

Two distinctly different types of sandstone are found in the Reserve.

One forms low stony ridges while the other has weathered to form interesting sandstone pillars known as ‘Lost City’ formations. The pillars are up to 25 metres high and contrast strongly with the surrounding countryside.

The colorful spires of the Lost City were formed when layer upon layer of sand was deposited and compacted the layers below them. 

The sand deposits were buried and the pressure of overlaying deposits along with tiny particles of clay that found their way in between the sand grains worked together to create sandstone.

The ripples on the rock are similar to those formed on a sandy beach at low tide, they indicate that the surface was laid down in shallow water.

The ripples are revealed when breaks happen along bedding planes, or areas of weakness that are created between layers with different particle sizes and hardness. 

The sandstone at Caranbirini was originally laid down as one massive sandstone block but pressure from within the earth’s crust raised it and caused vertical fracture lines known as joints.

Water moving along the joints has slowly eroded the rocks into chasms and hollows and in time the surrounding landscape was eroded revealing the ‘organ pipe’ structures that you can see all along the Barrawulla Track. 

Take a moment to travel through time and tack a visit to Caranbirini onto your next fishing trip to the Gulf.