RV Investigator is Australia's dedicated ocean research vessel that is operated by our Marine National Facility.
The vessel is equipped with an extensive array of advanced seabed mapping instrumentation that allows data to be collected in 3D faster than ever before.
The combination of systems allows high quality and large quantities of data to be collected from any depth in our marine estate.More information about RV Investigator
The Geophysical Survey and Mapping (GSM) team work aboard RV Investigator.
They operate its extensive array of sonar mapping sensors in support of the collaborative research delivered by our Marine National Facility.
The team oversees the acquisition, processing and management of the vast amounts of seabed data acquired by the ship.
The GSM team produce a range of seabed mapping products including 3D seabed models. These models give us a window to the ocean depths and helps scientists to understand some of its hidden secrets.
Learn about Australia's seamounts and how they form.
Seamounts are large undersea mountains that rise over 1,000 metres above the ocean floor and are generally associated underwater volcanoes, many of which are extinct.
They vary in size and shape. Diameters at the base can span from several kilometres to over 100 kilometres. Shapes range from conical to elongate and summits can be cone-shaped or flat-topped.
Seamounts are abundant in the world’s oceans and scientists estimate there to be over 14,200 of these impressive geological features globally. A further 100,000 are thought to exist of the smaller variety (less than 1,000 metres in elevation), and while often referred to as seamounts, are more accurately termed knolls (500-1000 metres tall) and abyssal hills (less than 500 metres tall).
This animation shows some of the visualisation that CSIRO’s geophysical survey and mapping team have created using data collected from RV Investigator. Seamount features are shown from the Tasman and Coral Seas including the Tasmantid and Lord Howe seamount chains.
Specific seamounts shown include the Scoparia, Janszoon, Lanceolata, Janzoon, Galaxiid, Zeehan, Heemskirk, Awatea. GEBCO datasets are used alongside multibeam ‘swath’ bathymetry datasets.Hide transcript
The distribution of seamounts varies considerably across the globe, with the greatest concentration found in the Pacific Ocean, followed by the Atlantic Ocean, Indian Ocean, and to a far lesser extent in the Southern Ocean (where they are rarer and more isolated).
Globally seamounts are estimated to occupy less than 1 per cent of the total area of the ocean floor.
Although most commonly located near tectonic plate boundaries, seamounts are also found in mid-plate regions, where they often form in linear groups known as chains.
The formation of these seamount chains is linked to hotspots — places where plumes of magma rise through the mantle to the crust.
Many seamounts were once volcanic islands above sea-level but gradually, over millions of years, they sank below the surface of the ocean as the crust below them cooled and became denser.
During this period of subsidence, some underwent prolonged erosion at their summits causing many to have had their tops flattened — these are called guyots (pronounced gee-yo).
Whilst many people are familiar with the popular seamounts and volcanoes associated with the Hawaiian chain, few are aware of the seamounts in Australian waters.
The Tasmantid seamount chain is a great example — consisting of 16 extinct volcanoes (some with elevations >4,000 m) and aged from 6 to 40 million years old, this seamount chain spans 2,000 km across the Coral & Tasman Seas. It lies parallel to another seamount chain located further seawards, called the Lord How chain, to which Lord Howe island belongs.
Our research voyages continue to unlock the science behind seamounts.
Learn more about submarine canyons and the tech used to visualise them.
Surrounding Australia are over 750 submarine canyons. These canyons play a crucial role in supporting and regulating our ocean environment.
Extending out from our Australian coastline is the continental shelf, the shallow extension of the Australian landmass. Beyond this shelf the seabed drops steeply down the continental slope onto the abyssal plains.
Within this continental slope deep incisions have been made into the seabed, carving out steep-sided valleys, these are called submarine canyons many of which dwarf their terrestrial counterparts.
Some submarine canyons have followed the paths of ancient river courses that meandered their way out to the continental shelf break where ocean currents and landslides have continued their paths creating grand canyons.
Other submarine canyons and their tributaries have formed when sections of the continental slope have slipped away over time in a process similar to terrestrial landslides. These submarine landslides, as they are called, create large ‘turbity’ currents which continue the cycle of seabed erosion and canyon building.
Submarine canyons are considered to be major conduits transporting significant amounts of sediment to the deep ocean floor.
Canyons can also act as conduits for upwelling, a process whereby deep, cold and nutrient rich waters are lifted towards the surface. Upwelling provides a thriving condition for a diverse assortment of marine life.
Bremer Canyon, off the coast of Bremer Bay, WA, is one of Australia’s marine biodiversity hotspots. It starts atop the continental shelf in 100–200 metres of water before plunging to abyssal depths of over 4000 metres. It is home to an abundance of marine life including high numbers of orca, whales and giant squid.
By mapping submarine canyons, we are acquiring data which underpins much of our understanding of these unique and important marine environments.
Oceanic Ridges, or undersea mountain ranges, exist throughout the world’s oceans and rise from the oceans depths as steep sided, linear features.
Ocean ridges can rise kilometres above the seabed and can span the lengths of oceans.
They are formed through a range of processes which are largely influenced by plate tectonics. Some forms of ocean ridges include spreading-centre ridges, fracture-zone ridges and basaltic-volcanic ridges.
Many of the oceans ridges form at the boundaries of tectonic plates although they can also form above ‘hotspots’ in the earth’s mantle.
The mid ocean ridge system is the longest mountain range on Earth spanning over 60,000 km around the globe.
4000 kilometres south west of Perth. Williams Ridge (80°30′S 29°20′W Coordinates: 80°30′S 29°20′W) is a conspicuous rock ridge, 1,060 m, extending east-west between Blaiklock and Stratton Glaciers, 1 nautical mile (1.9 km) northwest of Honnywill Peak in the west part of the Shackleton Range.
Mapped in high resolution by RV Investigator. Over 37,000 square kilometres of seabed mapped.Hide transcript
William’s Ridge is an oceanic ridge which is part of the Kerguelan Plateau in the Southern Ocean.
It is close to Australia’s World Heritage listed Heard and Macdonald Islands.
The ridge was mapped by RV Investigator as part of a 60-day voyage south-west of Australia.
This mapping enabled a comprehensive model of the Ridge to be developed and is helping to better understand the region.
This data will also support Australia in a submission to claim sovereignty over new seafloor under the United Nations Conventions on the Law of the Sea (UNCLOS).
An estimated three million shipwrecks litter the oceans across the globe, and around 8,000 of these are believed to lie around the shores of Australia.
Some shipwrecks date back to the dawn of sea-travel for trade and early human exploration. Shipwrecks continue into the present day, as ships remain an important form of transport for cargo and passengers alike.
Fortunately, with the ever-improving sophistication of modern technologies, the oceans have been and are continuing to be mapped in far greater detail than ever before.
This together with highly accurate navigational systems, has made seafaring far safer in the present day however, accidents still occur and wrecks continue to be claimed by our oceans.
Shipwrecks mapped by the CSIRO geophysical survey and mapping team in order appearing in this video:
To many people, ancient shipwrecks are fascinating and alluring, often due to the mystery surrounding them and potential riches that they are thought to hold.
For maritime archaeologists however, they are a window into our past and these scientists work at piecing together complex puzzles of human history.
Many shipwrecks have disappeared without trace and often with a significant loss of life too — sadly these often endure as unsolved mysteries and their stories go untold.
Our research voyages often contribute to the discovery, location and mapping of previously unknown or poorly charted shipwrecks.
Some of the more famous examples include the SS Macumba (located in 2017), SS Federal (mapped in 2019) & the SS Iron Crown (located in 2019).
Researchers on our research vessel Investigator have solved a maritime mystery 74 years in the making with the discovery of the wreck of SS Macumba, a merchant ship sunk by Japanese air attack during Word War II.
The SS Iron Crown, a 100 meter-long ore freighter, was sunk by a Japanese submarine on 4 June 1942 while travelling through Bass Strait with a cargo of manganese ore. The heavily loaded freighter was hit by a torpedo from the submarine and sank within 60 seconds.
When ice shelves and glaciers break apart, in a process known as ‘calving’, they form what we know as icebergs.
Once calved the icebergs are set adrift to float with the ocean currents.
As the ice bergs are formed primarily of freshwater, or pure ice water, they are able to float on the denser seawater
The floatation of an iceberg is generally only sufficient to expose a small portion of the iceberg above the surface with the bulk of the volume remaining below the surface.
When an iceberg drifts into shallow waters it’s base, or keel, can come into contact with the seabed.
As an iceberg’s keel contacts the seabed its scrapes out significant gouges in the seabed, and these are referred to as iceberg scours.
Our research voyages to the Southern Ocean, and to the Antarctic ice edge, have allowed for iceberg scours to be mapped in great detail.
By mapping these features we provide valuable data that allows scientists to better understand the worlds ocean currents and climate.
Read more about the geophysical survey and mapping equipment used aboard RV Investigator.Visit the site
Access our collection of seabed mapping data.Access the data