Using advanced satellite imagery, Curtin University researchers and international collaborators discovered an ancient reef-like landform “hidden” in plain sight on the Nullarbor Plain that has been preserved for millions of years since it formed when the Plain was underwater.
Dr. Milo Barham, from Curtin’s School of Earth and Planetary Sciences’ Timescales of Mineral Systems Group, said the discovery challenged the notion that the Nullarbor Plain, which emerged from the ocean about 14 million years ago, was essentially flat and featureless.
“In contrast to many other parts of the world, large areas of the Nullarbor Plain have remained largely unchanged by weathering and erosion processes over millions of years, making it a unique geological canvas recording ancient history in remarkable ways,” Dr. Barham said.
“Through high-resolution satellite imagery and fieldwork, we discovered the clear remnant of an original seabed structure preserved for millions of years, which is the first of its kind discovered on the Nullarbor Plain.”
The ring-shaped ‘hill’ cannot be explained by extraterrestrial impact or any known deformation processes, but it does preserve original microbial textures and features characteristic of the modern Great Barrier Reef.”
The discovery, according to Dr. Barham, was made possible by increased access to new high-resolution satellite imagery, which revealed subtle features representing surprising histories of environmental evolution on the Nullarbor Plain.
“Evidence of long-gone river channels, as well as sand dune systems imprinted directly into limestone, preserve an archive of ancient landscapes and even a record of the prevailing winds.” It’s not just landscapes. Dr. Barham explained that “isolated cave shafts punctuating the Nullarbor Plain preserve mummified remains of Tasmanian tigers and complete skeletons of long-extinct wonders such as Thylacoleo, the marsupial lion.”
“At the surface, the Nullarbor Plain has preserved large quantities of meteorites due to the relatively stable conditions, allowing us to peer back in time to the origins of our solar system.”
“These features, combined with the millions of years old landscape feature we’ve now identified, effectively make the Nullarbor Plain a land that time forgot, allowing for a fascinating deeper understanding of Earth’s history.”
Dr. Barham is a member of Curtin’s flagship Earth Sciences research institute, The Institute for Geoscience Research (TIGeR).
The study, titled “Enigmatic annular landform on a Miocene planar karst surface, Nullarbor Plain, Australia,” was led by Dr. Matej Lipar of the Anton Melik Geographical Institute at the Slovenian Academy of Sciences and Arts and will be published in Earth Surface Processes And Landforms.