The researchers have used a technique pioneered by the university’s Professor Jon Woodhead to test the age of the samples taken from the cave floors.

Using the technique, called uranium-lead dating, the researchers found the mountains in south-east Victoria are growing 76 metres every million years.

“So that may not sound like a whole lot to you and me. But on a geological timescale, that’s actually quite a lot,” PHD student and researcher John Engel said.

Usually, tension between tectonic plates causes mountains to grow.

For example, Mr Engel said, mountains like those in the Himalayas are growing about 250 metres every million years.

But Australia’s mountains are different because they are not on the edge of a tectonic plate.

Previously, geologists believed the caves were 90 million years old. But the Melbourne University team believes they are much younger.

“This new research shows that the caves started forming around three-and-a-half million years ago,” Mr Engel said.

The previous estimates were based on rock samples taken from nearby parts of Victoria’s highlands.

“Our research doesn’t discredit that; it just shows that there’s been additional younger pulses of uplift that have happened,” he said.

Using uranium-lead testing on broken pieces of cave stalactites and stalagmites — collectively known as speleothems — marks a shift in how young mountains are dated.

Previously, geologists would use a technique called apatite fission track dating, which Mr Engel said wasn’t suited to dating younger mountains.

“Anything younger than about 15 million years old is really hard to see by the apatite fission track dating and techniques,” he said.

“So this new speleothem cave-based one we hope will be an exciting and useful way for geologists around the world to show young uplift.”

https://www.abc.net.au/news/2020-05-24/buchan-caves-not-as-old-as-previously-thought/12279612

Oh thanks mate, there was me thinking they were much older and you had to come along and spoil it for me

PermeateFree said:

The researchers have used a technique pioneered by the university’s Professor Jon Woodhead to test the age of the samples taken from the cave floors.

Using the technique, called uranium-lead dating, the researchers found the mountains in south-east Victoria are growing 76 metres every million years.

“So that may not sound like a whole lot to you and me. But on a geological timescale, that’s actually quite a lot,” PHD student and researcher John Engel said.

Usually, tension between tectonic plates causes mountains to grow.

For example, Mr Engel said, mountains like those in the Himalayas are growing about 250 metres every million years.

But Australia’s mountains are different because they are not on the edge of a tectonic plate.

Previously, geologists believed the caves were 90 million years old. But the Melbourne University team believes they are much younger.

“This new research shows that the caves started forming around three-and-a-half million years ago,” Mr Engel said.

The previous estimates were based on rock samples taken from nearby parts of Victoria’s highlands.

“Our research doesn’t discredit that; it just shows that there’s been additional younger pulses of uplift that have happened,” he said.

Using uranium-lead testing on broken pieces of cave stalactites and stalagmites — collectively known as speleothems — marks a shift in how young mountains are dated.

Previously, geologists would use a technique called apatite fission track dating, which Mr Engel said wasn’t suited to dating younger mountains.

“Anything younger than about 15 million years old is really hard to see by the apatite fission track dating and techniques,” he said.

“So this new speleothem cave-based one we hope will be an exciting and useful way for geologists around the world to show young uplift.”

https://www.abc.net.au/news/2020-05-24/buchan-caves-not-as-old-as-previously-thought/12279612

> the mountains in south-east Victoria are growing 76 metres every million years.

That’s rather startling really. Australia’s mountains are not supposed to be actively growing.

mollwollfumble said:

PermeateFree said:

The researchers have used a technique pioneered by the university’s Professor Jon Woodhead to test the age of the samples taken from the cave floors.

Using the technique, called uranium-lead dating, the researchers found the mountains in south-east Victoria are growing 76 metres every million years.

“So that may not sound like a whole lot to you and me. But on a geological timescale, that’s actually quite a lot,” PHD student and researcher John Engel said.

Usually, tension between tectonic plates causes mountains to grow.

For example, Mr Engel said, mountains like those in the Himalayas are growing about 250 metres every million years.

But Australia’s mountains are different because they are not on the edge of a tectonic plate.

Previously, geologists believed the caves were 90 million years old. But the Melbourne University team believes they are much younger.

“This new research shows that the caves started forming around three-and-a-half million years ago,” Mr Engel said.

The previous estimates were based on rock samples taken from nearby parts of Victoria’s highlands.

“Our research doesn’t discredit that; it just shows that there’s been additional younger pulses of uplift that have happened,” he said.

Using uranium-lead testing on broken pieces of cave stalactites and stalagmites — collectively known as speleothems — marks a shift in how young mountains are dated.

Previously, geologists would use a technique called apatite fission track dating, which Mr Engel said wasn’t suited to dating younger mountains.

“Anything younger than about 15 million years old is really hard to see by the apatite fission track dating and techniques,” he said.

“So this new speleothem cave-based one we hope will be an exciting and useful way for geologists around the world to show young uplift.”

https://www.abc.net.au/news/2020-05-24/buchan-caves-not-as-old-as-previously-thought/12279612

> the mountains in south-east Victoria are growing 76 metres every million years.

That’s rather startling really. Australia’s mountains are not supposed to be actively growing.

You forget that we were once volcanic and still have a little of that left yet to display itself.

roughbarked said:

mollwollfumble said:

PermeateFree said:

The researchers have used a technique pioneered by the university’s Professor Jon Woodhead to test the age of the samples taken from the cave floors.

Using the technique, called uranium-lead dating, the researchers found the mountains in south-east Victoria are growing 76 metres every million years.

“So that may not sound like a whole lot to you and me. But on a geological timescale, that’s actually quite a lot,” PHD student and researcher John Engel said.

Usually, tension between tectonic plates causes mountains to grow.

For example, Mr Engel said, mountains like those in the Himalayas are growing about 250 metres every million years.

But Australia’s mountains are different because they are not on the edge of a tectonic plate.

Previously, geologists believed the caves were 90 million years old. But the Melbourne University team believes they are much younger.

“This new research shows that the caves started forming around three-and-a-half million years ago,” Mr Engel said.

The previous estimates were based on rock samples taken from nearby parts of Victoria’s highlands.

“Our research doesn’t discredit that; it just shows that there’s been additional younger pulses of uplift that have happened,” he said.

Using uranium-lead testing on broken pieces of cave stalactites and stalagmites — collectively known as speleothems — marks a shift in how young mountains are dated.

Previously, geologists would use a technique called apatite fission track dating, which Mr Engel said wasn’t suited to dating younger mountains.

“Anything younger than about 15 million years old is really hard to see by the apatite fission track dating and techniques,” he said.

“So this new speleothem cave-based one we hope will be an exciting and useful way for geologists around the world to show young uplift.”

https://www.abc.net.au/news/2020-05-24/buchan-caves-not-as-old-as-previously-thought/12279612

> the mountains in south-east Victoria are growing 76 metres every million years.

That’s rather startling really. Australia’s mountains are not supposed to be actively growing.

You forget that we were once volcanic and still have a little of that left yet to display itself.

Not to mention that you haven’t been keeping up with tectonic plate movements and stuff.

Oh then again, you did use the words “not supposed”.