Tag Archives: geoscience

Earth recycles ocean floor into diamonds

Most diamonds are made of cooked seabed.

The diamond on your finger is most likely made of recycled seabed cooked deep in the Earth.

Traces of salt trapped in many diamonds show the stones are formed from ancient seabeds that became buried deep beneath the Earth’s crust, according to new research led by Macquarie University geoscientists.

Most diamonds found at the Earth’s surface are formed this way; others are created by crystallization of melts deep in the mantle.

In experiments recreating the extreme pressures and temperatures found 200 kilometres underground, Dr Michael Förster, Professor Stephen Foley, Dr Olivier Alard, and colleagues at Goethe Universität and Johannes Gutenberg Universität in Germany, have demonstrated that seawater in sediment from the bottom of the ocean reacts in the right way to produce the balance of salts found in diamond.

The study, published in Science Advances, settles a long-standing question about the formation of diamonds. “There was a theory that the salts trapped inside diamonds came from marine seawater, but couldn’t be tested,” says lead author Michael. “Our research showed that they came from marine sediment.”

Continue reading Earth recycles ocean floor into diamonds

Reducing the impact of earthquakes

Working together, researchers in Japan and Australia are getting better at predicting the areas most at risk from earthquakes.

They are also working together on ways to determine, within seconds of a warning, the scale and likely impact of an earthquake.
Rapid detection and warning systems combined with smart engineering saved many lives in the Great Japanese Earthquake of 2011. But the earthquake and the resulting tsunami were much bigger than geological modelling suggested. The reasons for that might be found in deep history.

Mapping the hazard

 

Big earthquakes may be separated by centuries or millennia. But earthquake hazard maps are based on information gathered since 1900 when modern seismographs came into use. It’s difficult to model events happening over millennia when you have not got deep historical information. Continue reading Reducing the impact of earthquakes

Australian Academy of Science medals

Harry Messel has been a powerful force in science education—from the Physics Foundation to textbooks and his establishment of International Science Schools. He was awarded the Academy Medal.

Simon McKeon is a prominent business leader and philanthropist who has made extensive contributions to Australian science and innovation including chairing the CSIRO Board and the agenda-setting McKeon report into medical research in Australia. He was awarded the Academy Medal.

The life and death of cells: Jerry Adams has advanced understanding of cancer development, particularly of genes activated by chromosome translocation in lymphomas. By clarifying how the Bcl-2 protein family controls the life and death of cells, he and his colleagues at the Walter and Eliza Hall Institute of Medical Research have galvanised the development of a promising new class of anti-cancer drugs. Jerry was awarded the 2014 Macfarlane Burnet Medal. Continue reading Australian Academy of Science medals