Moderator: Moderators
Wayne Harrison wrote:The second oldest known open cave is in the Guadelupe Mountains in New Mexico, US, which is 65 million years old. Most other famous caves, such as Postojna Cave in Slovenia, are thought to be only about 5 million years old, he said.
Amemeba wrote:It would be neat to know how a void could remain stable for such a long time.
Amemeba wrote:Hmm...fuzzy semantics. Paleozoic caves, then, remain caves although they are 300 million years filled with fill.
Amemeba wrote:Not that it much matters, but to me a "cave" has to have some geological continuity through time.
Sydney, Aug16: A series of limestone caves west of Sydney have been pronounced the oldest in the world, dating back 340 million years, according to Australian scientists.
The Jenolan caves, a popular tourist attraction, now surpass caves in New Mexico, approximately 90 million years old, as the oldest dated open caves on the planet.
Armstrong Osbourne, a scientist who helped date the caves, says it is a unique opportunity for tourists to walk around in caves so old.
"This is the oldest cave that we know of in the world which you can actually walk around in that's not filled up with solid rock", he said.
Australian scientists have only been able to access the dating research from the past two years, as it was previously only available to oil companies.
The researchers studied tiny amounts of radioactive potassium in clay to determine the age of the caves; however, before the significance of the clay was realised, it was used to repair sewer pipes because of its malleable composition.
IN June the Jenolan Caves in the Blue Mountains of NSW were dated at 340 million years old. This makes them the oldest known open caves in the world. One hundred million years before dinosaurs, when amphibians wandered through ferns and forests, warm water rose beneath the east coast of Australia, creating hollows under the earth. When the ground split, spewing molten lava and raining ash into watery openings, a fine clay formed. It is this clay that has made dating the caves possible.
Armstrong Osborne, a speleologist from the University of Sydney, led the research team that made the discovery. He's happily flustered when we meet. He has done three radio interviews, agreed to another four, taken calls from reporters and fielded inquiries from leading international journals. It is his moment. Even in academic terms, where a 50-year-old is a mid-career researcher, his moment has been a long time coming.
For 25 years, Osborne and other speleologists suspected the Jenolan Caves were many millions of years older than the few thousand widely accepted, but they had no way to prove it. He completed his PhD on Jenolan in the 1980s and was told it might not be passed because of its radical proposals. "Most people were convinced the caves were quite young and those of us who thought they were really old couldn't find any evidence. But not even I imagined they'd date as far back as hundreds of millions of years," he says........
Users browsing this forum: No registered users