Scientists to review seabed data

16:00, Nov 14 2011

High-profile scientists from around the world are meeting in Oamaru to review results from ocean drilling off the coast of South Canterbury last year.

Integrated Ocean Drilling Program scientists drilled four sites on the continental shelf off Canterbury, using the seafloor drilling ship, JOIDES Resolution, and recovered sediment cores going back as far as 35 million years.

The cores were analysed over 22 months and scientists involved will discuss their findings at the conference this week.

The main aim of the expedition was to learn more about the relationship between climate change and global sea levels during the past 35 million years.

Expedition co-chief scientist Craig Fulthorpe, of the University of Texas, said the long record of sea level changes contained in areas such as the Canterbury Basin could help scientists forecast how sea level might change in response to global warming.

"This ancient record is not easy to read because seafloor sediments are also affected by local tectonic, sedimentary and oceanographic processes that can obscure the global sea level record," Dr Fulthorpe said. "The expedition off the Canterbury coast was designed to untangle those confounding effects."


The Canterbury Basin was ideal for this work because its seafloor sediments recorded detailed information about climate and sea level because of the large amount of sediment outwash from the Southern Alps, he said. This information would be integrated with findings from northern hemisphere expeditions to provide a better understanding of global trends in sea levels.

It also allowed scientists to investigate what happened when the seaway between Australia and Antarctica opened around 30 million years ago, starting a strong ocean circulation pattern.

The expedition drilled the deepest hole ever drilled by the JOIDES Resolution in a single expedition at a depth of 1927m.It also set a second record when it recovered sediment core from the shallowest water site ever drilled by the same ship.

The conference will be held at the Kingsgate Hotel Brydone tomorrow and Thursday.

The Timaru Herald