A group of marine scientists is on a voyage along Australia's east coast, assessing tsunami risk, submarine landslides and deep marine canyons.
They are mapping the ocean floor, including some areas which have never been studied before, on a journey from Hobart to Brisbane.
The aim is to identify the risks from tsunami events triggered by submarine landslides, and to help develop ways to reduce those risks.
Marine scientists and students from the University of Newcastle and University of Sydney are involved in the project.
"We are interested in understanding how the edge of our continent which is underwater evolves over time," University of Newcastle's Associate Professor Hannah Power said.
"What we are really interested in is these very large features we see underwater which look like big underwater landslides.
"So, we are out here looking at how they form, what might trigger them, where that material from those big landslides might end up and whether or not that might cause a tsunami."
Submarine landslides
Research shows that submarine landslides have occurred along the east coast of Australia for about 15 million years and are expected to happen again in the future.
Associate Professor Power said they were potentially huge events.
"These things are several kilometres wide, up to 10-15 kilometres long … if all that material moves at once, it shifts the water column above it and that creates a wave that radiates outwards, and then can impact on the coastline," she said.
If such an event did occur, there would be little time to prepare, but Associate Professor Power said the risk to Australia's east coast communities was relatively low.
"The challenge of the tsunami that are caused by underwater landslides is because the landslides are so close to the coastline, we would get very little warning," she said.
"We are really lucky in Australia in that our tsunami risk is relatively low … we are fairly far away from regions around the planet that cause most of our tsunami, which are the underwater plate tectonic regions, where our oceanic and continental plates meet."
Expanding sea floor maps
Associate Professor Power said the research was helping expand Australia's currently limited sea floor maps.
"We have on this trip mapped already areas of sea floor that were never mapped before and that's really exciting.
"Around the whole of Australia, I think we have mapped about 25 per cent of our sea floor in high resolution so we have a long way to go."
The research crew is on board the CSRIO research vessel 'Investigator'.
The scientists are collecting sea floor rock samples and also investigating deep ocean features such as the Ulladulla underwater canyon and slope, Byron slide and canyon, and the Noosa canyon.
"At the moment we are in about 4,600 metres of water, so we have about four kilometres of water below us," Associate Professor Power said.
"We use the length of time that it's taken to reflect off the sea floor, and the speed at which sound travels in water, to work out the depth."
The research vessel is currently off the NSW North Coast and the voyage will finish at Port of Brisbane.
"We are now off to a site off Yamba, and then around the Byron region, all the way up to Fraser island," Associate Professor Power said.
"Hopefully we are training the next generation of marine scientists while also doing mapping in areas we've never mapped before."
