Washington, Aug 8 : Researchers from the University of Queensland have identified some of the oldest preserved organic matter on Earth, confirmed to be 3.5 billion year old.

The team of Dr Miryam Glikson and Professors Sue Golding and Lindsay Sly are the first to conclusively confirm the nature and source of the organic material.

"What we have found is the first visual confirmation of primitive microbial communities in what is considered to be the best preserved ancient organic matter on our planet," said Dr Glikson, lead author of the study.

Dr Golding said previous studies used indirect analytical methods that were only able to suggest microbial involvement, not confirm it.

"We used difficult and time-consuming electron microscope techniques to conclusively confirm the microbial remains. The integration of observational and micro-analytical techniques is unique to our approach," said Dr Golding.

Core drilling samples from Western Australia's Pilbara region were compared to primitive microbes found today in seafloor environments similar to those existing 3.5 billion years ago.

As Dr Glikson said, they found "a remarkable resemblance between the structures of the cultured microbial entities at their stage of disintegration and those of the ancient microbial remains".

The research appears in the scientific journal Precambrian Research.