Big find for CSIRO's Southern Surveyor

As a developer of systems that allow us to look into the hidden secrets of the oceans, Kongsberg Maritime has played its part in many amazing discoveries over the years. Scientists all over the world use our hydroacoustic technology to get a clear view on what is happening below the waves.

Detailed seafloor mapping obtained using the EM 300 multibeam echosounder system.
Rocks from the abyss more than 1.5 km below the surface.

Some projects support industry in locating and extracting vital resources or help scientists to present a stunning picture of the exotic plant and animal life below the surface. Other projects, like a recently concluded survey aboard the Commonwealth Scientific and Industrial Research Organisation's (CSIRO) RV Southern Surveyor, help us peer into the past, giving a greater understanding of the geology that has shaped our world. Researchers from the University of Sydney, Macquarie University and the University of Tasmania led an international team of scientists on the voyage to map the seafloor of the Perth Abyssal Plain. The expedition returned to Perth in November after a three-week voyage, bringing with them results that really do ignite the imagination.

Looking into the past

In the remote waters of the Indian Ocean, west of Perth, scientists aboard RV Southern Surveyor discovered two sunken islands, almost the size of Tasmania, which were once part of the supercontinent Gondwana.

In the Cretaceous period when dinosaurs roamed the Earth (more than 130 million years ago), India was adjacent to Western Australia. When India began to break away from Australia, the islands formed part of the last link between the two continents.

Eventually these islands, referred to as 'micro-continents' by scientists, were separated from both landmasses and stranded in the Indian Ocean, thousands of kilometres from the Australian and Indian coasts.

"The data collected on the voyage could significantly change our understanding of the way in which India, Australia and Antarctica broke off from Gondwana," said Dr Joanne Whittaker, a postdoctoral fellow at the University of Sydney's School of Geosciences.

Sophisticated instruments

Helping the scientists to acquire this data was the suite of Kongsberg Maritime hydroacoustic sensors and systems aboard the RV Southern Surveyor, which included:

  • Simrad EK60 scientific echo sounder
  • Simrad EK500 scientific echo sounder
  • KONGSBERG EA 500 hydrographic echo sounder
  • KONGSBERG EM 300 multibeam hydrographic echo sounder
  • KONGSBERG PS 018 Sub-bottom profiler

Travelling on RV Southern Surveyor the scientists discovered the islands through detailed seafloor mapping using the EM 300 multibeam system and by the challenging collection of rocks from the abyss more than 1.5 km below the surface. The collection of the rocks was a key aspect to the mission according to the University of Sydney's Dr Simon Williams, the chief scientist on the expedition, who commented: "A detailed analysis of the rocks dredged up during the voyage will tell us about their age and how they fit into the Gondwana jigsaw".

The seafloor mapping using the KONGSBERG equipment provided a very clear view of the geology below the surface. The scientists were presented with stunning images of the underwater land masses. This was a vital element of the data that the team brought back with them.

"Our preliminary analysis of the magnetic data that we collected could cause us to rethink the whole plate tectonic story for the whole of the eastern Indian Ocean," added Dr. Whittaker.

The expedition took place aboard Australia's Marine National Facility's Research Vessel Southern Surveyor, which is owned and managed by CSIRO. The operations are funded by the Australian government and overseen by a government-appointed steering committee.