Ancient rock collisions may have formed Western Australia

Mar 30, 2007

A new 3D picture of the geology of Western Australia, captured by measuring seismic waves from deep in the Earth’s crust, has provided evidence that it was created when vast regions of ancient world slammed into each other.

Using a high concentration of seismic stations located all over remote parts of the Western Australia outback, Dr Anya Reading and colleague Professor Brian Kennett from the Research School of Earth Sciences have developed the clearest picture yet of the geology of the ancient rocks in the region, some of which date back 3.5 thousand million years.

Seismic stations measure the energy waves that reverberate throughout the Earth’s crust after earthquakes. The waves travel through different types of rock at different speeds, and by analysing the measurements of these velocities through the seismic stations, researchers can ‘map’ the underlying geology.

“Essentially, we get a picture of the geological structure of the deep crust through differences in the waveform ‘wiggles’,” Dr Reading, who is now based at the University of Tasmania, said.

The data the team obtained showed that the rock types of the different ‘crustal blocks’ that make up this ancient region are consistent across particular regions of the Earth’s crust.

“We found there were very clear delineations between the blocks of certain types of rock that make up the region, suggesting to us that these crustal blocks slammed together,” Dr Reading said.

The research team, including senior technical officer Steve Sirotjuk, collected the comprehensive 3D data by deploying more seismic recording stations across the region than had been before, giving more comprehensive data on the deep geology of the region.

“Although more work is needed to confirm how this ancient – and resource rich – area of the world formed, it is clear that this method of seismic station deployment could be used to get more accurate data about the deep geology of the Earth in other parts of the world,” Dr Reading said.

Source: ANU

Explore further: Researchers continue to investigate effects of military munitions

add to favorites email to friend print save as pdf

Related Stories

Insider trading study shows stronger enforcement

6 minutes ago

The first major study of the enforcement of Australia's insider trading laws has shown the number of insider trading cases brought by the Australian Securities and Investment Commission (ASIC) is increasing, ...

Study examines effects of credentialing, personalization

44 minutes ago

Chris Gamrat, a doctoral student in learning, design and technology, recently had his study—completed alongside Heather Zimmerman, associate professor of education; Jaclyn Dudek, a doctoral student studying learning, design ...

New evidence on Neanderthal mixing

46 minutes ago

New research on a 45,000-year-old Siberian thighbone has narrowed the window of time when humans and Neanderthals interbred to between 50,000 and 60,000 years ago, and has shown that modern humans reached ...

Recommended for you

NASA image: Fires in the southern United States

23 hours ago

In this image taken by the Aqua satellite of the southern United States actively burning areas as detected by MODIS's thermal bands are outlined in red. Each red hot spot is an area where the thermal detectors ...

User comments : 0