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20,000 times higher than atmospheric pressure as silica, or silicon dioxide, reacts with liquid hydrogen to form liquid water and silicon hydride. The results of these computer simulations have just been reported by Zdenek Futera at the University College Dublin in Ireland and his collaborators. This latest work simulates this reaction under various temperatures and pressures typical of the upper mantle between 40 and 400 kilometers down. It backs up previous work by Japanese researchers who performed and reported the reaction itself in 2014. So what was new about this latest study? Team member John Tse at the University of Saskatchewan in Canada commented, “We set up a computer simulation very close to their experimental conditions and simulated the trajectory of the reaction.” But, surprisingly, they found that “the hydrogen fluid diffuses through the quartz layer, but ends up forming water not at the surface, but in the bulk of the mineral,” according to Tse. “We analyzed the density and structure of the trapped water, and found that it is highly pressurized.”

DEEP EARTHQUAKES The authors also found that the pressure could reach as high as 200,000 atmospheres. The research team therefore suggested that this new water may be under so much pressure that it can trigger earthquakes hundreds of kilometers below the Earth’s surface, tremors whose origins have so far remained unexplained. “We observed the water to be at high pressure, which might lead to the possibility of induced earthquakes,” says Tse. The earthquakes could be triggered as the water finally escapes from the crystals. The occurrence of deep earthquakes in the uppermost mantle lithosphere beneath stable cratons (the foundational cores of continents) are known but remain enigmatic in their origin. For example, the 2013 Wind River (Wyoming) earthquake occurred at 75 ± 8 kilometers, well beneath the base

november 2017 / Impacto evangelistic

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766_English  

Magazine Evangelistic Impact Edition November 2017 English language

766_English  

Magazine Evangelistic Impact Edition November 2017 English language

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