Tip:
Highlight text to annotate it
X
This recreation of Australia breaking away from the Antarctic
is 100 million years racing before your eyes.
And it reveals for the first time
the puzzle of the disappearance of Australia's great inland sea.
Dr Moresi - "The puzzling thing about the Australian plate is that 100 million years ago,
"when sea levels everywhere were at their lowest, Australia was actually flooded,
"but then 20 million years or so later,
"sea levels were much higher but Australia was actually dry".
Like all continents, Australia is a thin crust of the lightest rock material,
only about 20 to 50 kilometres deep,
that drifts and bobs in response to the vast churning of the earth's internal heat engine.
And the shifting and collision of tectonic plates creates mountain ranges and volcanoes.
But this didn't answer the question of why the inland sea disappeared.
So CSIRO scientists created a computer model of the changes that have occurred
ever since Australia broke away from the Antarctic.
And for the first time were able to see just how much it has drifted, bobbed and bent.
Dr Moresi - "Well, we took all the available data
"and we took a conceptual model of how we think that the earth operates
"and we combined those two to make a computer program
"which would be capable of modelling how the earth works".
Millions of years ago, the Australian plate was sucked down by some 350 metres,
by a second tectonic plate, shown in purple, this allowed the seas to flood low lying areas.
Then, as the continent drifted north
gradually escaping from the influence of the underlying plate,
the shallow seas that had covered it disappeared.
Later when sea levels rose, the sediment left behind by the seas,
made the land surface high enough to remain dry.
This animation not only shows for the first time how Australia was formed,
it is expected to be a valuable tool in the hunt for oil and minerals.
Helping geologists better understand
how a particular piece of ground was formed and what lies below.