Thursday, August 24, 2006

Australian Geologists Date World's Oldest Discovered Open Caves At 340 Million Years

The Persian Chamber in the Orient Cave: research
has dated Jenolan Caves at 340 million years old.
Cave-dating research published by Australian geologists has found that the Jenolan Caves, in central NSW, are the world's oldest discovered open caves.

In a study published in the June issue of the Australian Journal of Earth Sciences (Vol. 53, 377-405), scientists from CSIRO, the University of Sydney and the Australian Museum -- in cooperation with the Jenolan Caves Trust -- have shown that the limestone caves, which attract thousands of tourists each year, date back more than 340 million years.

Until 20 years ago most scientists thought the Jenolan Caves were no more than a few thousand years old. In 1999 geologists estimated that the caves might be between 90 and 100 million years old.

Dr Armstrong Osborne, a senior lecturer at the University of Sydney, has long suspected that the caves are older than had been widely recognised, but says he was surprised to find they dated back to the Carboniferous (290 to 354 million years ago).

"We've shown that these caves are hundreds of millions of years older than any reported date for an open cave anywhere in the world," Dr Osborne says.

"Even in geological terms, 340 million years is a very long time. To put it into context, the Blue Mountains began to form 100 million years ago; dinosaurs became extinct 65 million years ago, and Tasmania was joined to the mainland as recently as 10,000 years ago.

Thursday, August 24, 2006

Australian Geologists Date World's Oldest Discovered Open Caves At 340 Million Years

The Persian Chamber in the Orient Cave: research
has dated Jenolan Caves at 340 million years old.
Cave-dating research published by Australian geologists has found that the Jenolan Caves, in central NSW, are the world's oldest discovered open caves.

In a study published in the June issue of the Australian Journal of Earth Sciences (Vol. 53, 377-405), scientists from CSIRO, the University of Sydney and the Australian Museum -- in cooperation with the Jenolan Caves Trust -- have shown that the limestone caves, which attract thousands of tourists each year, date back more than 340 million years.

Until 20 years ago most scientists thought the Jenolan Caves were no more than a few thousand years old. In 1999 geologists estimated that the caves might be between 90 and 100 million years old.

Dr Armstrong Osborne, a senior lecturer at the University of Sydney, has long suspected that the caves are older than had been widely recognised, but says he was surprised to find they dated back to the Carboniferous (290 to 354 million years ago).

"We've shown that these caves are hundreds of millions of years older than any reported date for an open cave anywhere in the world," Dr Osborne says.

"Even in geological terms, 340 million years is a very long time. To put it into context, the Blue Mountains began to form 100 million years ago; dinosaurs became extinct 65 million years ago, and Tasmania was joined to the mainland as recently as 10,000 years ago.