The Pinnacles Desert: Nambung National Park

The Pinnacles

On the first day of our journey, we venture to the Pinnacles Desert, home to the eerie, ancient rock formations that rise dramatically from the golden sands. Located in Nambung National Park, just 200km north of Perth, this surreal landscape is a must-see for any nature enthusiast. The Pinnacles Desert offers an unforgettable experience, where you can explore these unique spires at your own pace, taking in the breathtaking views and capturing memories along the way.

The Pinnacles Desert is home to stunning limestone pillars that have been sculpted over the course of 25,000 to 30,000 years, creating a truly otherworldly landscape.

​These majestic rock formations are the result of marine life from an earlier era, where seashells were broken down into lime-rich sands. Over time, these sands were blown inland, forming towering dunes. While the precise process that transformed these sands into the iconic columns we see today remains a mystery, three major theories have been proposed to explain the formation of the Pinnacles Desert.

The Science Bit

The first theory states that they were formed as dissolutional remnants of the Tamala Limestone, i.e. that they formed as a result of a period of extensive solutional weathering (karstification). Focused solution initially formed small solutional depressions, mainly solution pipes, which were progressively enlarged over time, resulting in the pinnacle topography. Some pinnacles represent cemented void infills (microbialites and/or re-deposited sand), which are more resistant to erosion, but dissolution still played the final role in pinnacle development.

A second theory states that they were formed through the preservation of tree casts buried in coastal aeolianites, where roots became groundwater conduits, resulting in the precipitation of indurated (hard) calcrete. Subsequent wind erosion of the aeolianite then exposed the calcrete pillars.

A third proposal suggests that plants played an active role in the creation of the Pinnacles, based on the mechanism that formed smaller "root casts" in other parts of the world. As transpiration drew water through the soil to the roots, nutrients and other dissolved minerals flowed toward the root—a process termed "mass-flow" that can result in the accumulation of nutrients at the surface of the root, if the nutrients arrive in quantities greater than that needed for plant growth. In coastal aeolian sands that consist of large amounts of calcium (derived from marine shells), the movement of water to the roots would drive the flow of calcium to the root surface. This calcium accumulates at high concentrations around the roots and over time is converted into a calcrete. When the roots die, the space occupied by the root is subsequently also filled with a carbonate material derived from the calcium in the former tissue of the roots, and possibly also from water leaching through the structures. Although evidence has been provided for this mechanism in the formation of root casts in South Africa, evidence is still required for its role in the formation of the Pinnacles.
​Source: kids.kiddle.co

​Whichever theory you choose, the Pinnacles truly are a magnificent sight and a special stop on our tour.

We recognise and acknowledge Yued people as the traditional custodians of Nambung National Park