Free Newsletters - Space News - Defense Alert - Environment Report - Energy Monitor
by Staff Writers
Potsdam, Germany (SPX) Jun 17, 2013
Water in the Earth's crust and upper mantle may not play such an important role as a lubricant of plate tectonics as previously assumed. This is a result geoscientists present in the current issue of the scientific journal Nature (13/06/2013) after the examination of water in the mineral olivine.
Laboratory experiments over the past three decades have suggested the presence of water greatly weakens the mechanical strength of the mineral olivine, a key component of the Earth's upper mantle.
In a recent study led by the Bayerisches Geoinstitut in Bayreuth, the Secondary Ion Mass Spectrometer (SIMS) facility at the Potsdam based GFZ German Research Centre for Geosciences was used to reassess the importance of water in defining the rigidity of olivine.
While earlier studies were based on mineral aggregates, the SIMS method enabled a look at the role of water in single olivine crystals at the near-atomic scale.
Michael Wiedenbeck, who conducted the SIMS experiment at the GFZ: "We discovered that water has a much, much lower effect in terms of the mechanical weakening of olivine as previously believed.
The new observations call for a reassessment of the role of water within the Earth's interior." One important consequence is that the earlier concept, indicating that water provides lubrication for continental drift, needs to be carefully reconsidered.
Hongzhan Fei, Michael Wiedenbeck, Daisuke Yamazaki and Tomoo Katsura - Small effect of water on upper-mantle rheology based on silicon self-diffusion coefficients. DOI: 10.1038/nature12193; vol 498; issue 7453; pp. 213-215
Helmholtz Association of German Research Centres
Space Technology News - Applications and Research
|The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement|