A new study published in the Proceedings of the National Academy of Sciences on Nov. 2 has cited x-rays that suggest an ocean of magma used to sit atop the core of the Earth 4.5 billion years ago, according to a press release. Although scientists previously believed that a magma ocean existed in the lowermost section of the Earth's mantle, this hypothesis was never tested through experimental research.
The scientists focused their x-rays, which were generated with the help of the European Synchrotron, Grenoble, France (ESRF), on bridgmanite, which is the most abundant mineral that exists deep inside the Earth and is made up of silicon, oxygen and magnesium atoms. When bridgmanite melts, its atoms become disorganized and the mineral becomes the amorphous magnesium-silicate, which is the molten rock that they believe sunk into the lowermost parts of the mantle on top of the Earth's core.
"Coming originally from a scientific background related to geosciences, I am very pleased to see how synchrotron micro-beam experiments can help to elucidate fundamental questions about the composition of our planet," said Manfred Burghammer of the ESRF, who participated in the research. "I think that this method bears a high potential regarding similar scientific questions in this field."
Bridgmanite is also believed to contain thorium and uranium, two minerals that are abundant in the rocks of Hawaii.
"A basal magma ocean would be an ideal candidate to explain [that feature]," said Sylvain Petitgirard, lead author of the study. "There is really a lot of work to do to understand our planet,"
