Hot springs offer clue to life on Mars

Dr Bridget Lynne with a 6000-year-old tree trunk fossilised in silica. Her research focuses on the Orakei Korako springs at left. Picture / Paul Estcourt

New Zealand hot springs may help answer one of the eternal questions in science: Is there life on Mars?

For the past two years, Auckland geologist Bridget Lynne has commuted to Orakei Korako near Taupo to study the formation and transformation of silica rocks placed inside a fumarole, an acidic steam vent of approximately 95C.

Dr Lynne's study into the geothermal environment may hold the key to identifying fossilised remains on Mars and in ancient earth rocks.

Its significance has already attracted the attention of Professor Jack Farmer, the leading scientist on Nasa's 2004 Mars Twin Rover Mission, who came to New Zealand for two weeks to see the study.

Ancient hot springs are believed to have occurred on Mars, and these extreme environments are thought to be a likely place to have hosted microbial life.

The silica that is deposited in these sites coats, entombs and fossilises the microbes living in the area.

The silica transforms over time, eventually becoming quartz.

At Orakei Korako, patches of quartz were seen within 21 weeks - when previous research had suggested that quartz took thousands of years to form.

The findings would allow for better analysis of rocks and in identifying the fossil layers within those rocks, said Dr Lynne.

"This research will have international significance, not only for looking at fossils in ancient earth rocks, but in looking at ancient rocks from Mars that might hold proof of life," said Dr Lynne.

Her PhD research, which appears in this month's issue of the journal Geology, documents the differences between natural deposits and deposits transformed by the intense environment.

Her work is part of the Sinter Programme headed by her PhD research supervisor, Auckland University Associate Professor Kathy Campbell, a former Nasa scientist.

Dr Campbell had invited Professor Farmer to see the programme in action.

"He decided that the work we were doing was of enough international interest and significance to come over and have a look at our system," said Dr Lynne.

The Sinter programme, named after rock that forms through the discharge of hot spring water, is enjoying international recognition that continues to grow, with visits from several other leading US and British hot-spring science specialists over the past few years.