Ancient jigsaw puzzle of super-continent Gondwana solved

Researchers have located the past position of the Australian, Antarctic and Indian tectonic plates, demonstrating how they formed the super-continent Gondwana 165 million years ago.

Researchers from Royal Holloway, The Australian National University and Geoscience Australia, helped clear up previous uncertainties on how the plates evolved and where they should be positioned when drawing up a picture of the past.

"The Earth's tectonic plates move around through time. As these movements occur over many millions of years, it has previously been difficult to produce accurate maps of where the continents were in the past," Dr Lloyd White from the Department of Earth Sciences said.

"We used a computer programme to move geological maps of Australia, India and Antarctica back through time and built a 'jigsaw puzzle' of the super-continent Gondwana. During the process, we found that many existing studies had positioned the plates in the wrong place because the geological units did not align on each plate," said White.

The researchers adopted an old technique used by people who discovered the theories of continental drift and plate tectonics, but which had largely been ignored by many modern scientists.

"It was a simple technique, matching the geological boundaries on each plate. The geological units formed before the continents broke apart, so we used their position to put this ancient jigsaw puzzle back together again.

"It is important that we know where the plates existed many millions of years ago, and how they broke apart, as the regions where plates break are often where we find major oil and gas deposits, such as those that are found along Australia's southern margin," White added.

The study was published in the journal Gondwana Research.