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Do Martians exist on that faraway planet orbiting the sun?
How did ancient mountain ranges and continents form, long before the age of dinosaurs?
An international research team led by earth sciences Prof. Desmond Moser at the University of Western Ontario is using three-billion-year-old data to try to answer those questions and more about deep, dark secrets held beneath the Earth's surface.
"It's pretty exciting," Moser says of the data his team has gleaned from zircon microcrystals collected in 2005 from southeast of Chapleau, in northern Ontario.
The crystals -- pushed to the Earth's surface from 30 kilometres below -- are opening a new window on how continents were formed and how natural resources, including gold and diamonds, originated. In his new microcrystal gross imaging Zercon Accessory Phase (ZAP) lab at Western, Moser's team may eventually be capable of magnifying crystals 100 times greater than existing technology allows, with funding sought through the Canadian Foundation of Innovation.
Right now, the deepest drill hole in the Earth is 10 kilometres, while the deepest mine, where humans actually labour, is only two kilometres, says Moser.
That's why the crystals -- pushed to the Earth's surface from 30 kilometres below -- are unmasking information humans have never before accessed, he says.
"Measuring no more than the width of a human hair, the 200-million-year growth span of these ancient microcrystals is longer than any previously discovered," he adds.
His team's research has discovered the crystals -- despite exposure to heat and pressure deep in the Earth -- haven't changed in status, but rather have "an incredible memory" of their time below volcanoes and now-extinct mountain ranges.
"These samples are from areas where, normally, humans can't touch," says Moser. "They provide a new record of planetary evolution."
Moser likens the microcrystals to "memory cells of the Earth."
"We can now say these crystals, containing trace amounts of uranium, continued to grow over hundreds of millions of years, even as the planet evolved and underwent dramatic shifts. These crystals are an accurate recorder of planetary evolution over eons -- in the same way rings on an old growth tree can record changes in a forest over hundreds of years.
"These crystals are incredibly resistant and have survived all these major forces that have destroyed other minerals, but these minerals have survived."
As for the practical application of his team's discovery, Moser says it offers new insight into the way the surface of our planet was behaving before the continents were created.
"A lot of people predicted these crystals would not keep their memory, but like elephants, these crystals held onto their chemical memory," says Moser.
"This information tells us something new about the formation of a very mineral-rich, diamond-rich part of the Earth and northern Ontario and northern Quebec in particular," he says. "It's not every day you find a piece of the Earth that you can walk around on and explore."
Moser's findings are detailed in the March issue of Geology.
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