By studying these strange looking chimney stacks, scientists are finding vital clues to how gold, silver and other precious metal ore bodies have been formed over billions of years.

This is CSIRO's research vessel "Franklin", on a voyage of discovery into the underwater volcanic zones near Papua New Guinea.

It's where the Australian Plate is being dragged beneath the Pacific Ocean plate in a region renowned for its major earthquakes and active volcanoes.

The scientists were sure they would find deposits of gold, silver and other precious minerals being formed on the seafloor...

And they did... The smoke being belched out by these three-metre high black chimneys is forming deposits rich in both copper and gold.

It turned out to be the richest deposit site, by far, ever discovered on the ocean bed and scientists believe it may be just the tip of an enormous ore forming system.

This exciting find, that they called the PACMANUS hydrothermal field, is in fact a natural underwater laboratory in the process of concentrating precious metals into ores. And by studying it, scientists are able to unravel how rich ore bodies were formed millions of years ago.

So far, these underwater mineral deposits are small, compared with land based deposits, but the knowledge gained from examining them as they are forming, is a boon for scientists.

It can be used in land based mineral exploration, to discover new and valuable sites of rich deposits of precious metals.