DOI: 10.1126/science.279.5349.358 , 358 (1998); 279Science et al.Edmundo Norabuena,America Convergence Across the Central AndesSpace Geodetic Observations of Nazca-South www.sciencemag.org (this information is current as of December 4, 2006 ):The following resources related to this article are available online at http://www.sciencemag.org/cgi/content/full/279/5349/358version of this article at: including high-resolution figures, can be found in the onlineUpdated information and services, http://www.sciencemag.org/cgi/content/full/279/5349/358#otherarticles, 5 of which can be accessed for free: cites 9 articlesThis article 75 article(s) on the ISI Web of Science. cited byThis article has been http://www.sciencemag.org/cgi/content/full/279/5349/358#otherarticles 9 articles hosted by HighWire Press; see: cited byThis article has been http://www.sciencemag.org/cgi/collection/geochem_physGeochemistry, Geophysics : subject collectionsThis article appears in the following http://www.sciencemag.org/help/about/permissions.dtl in whole or in part can be found at: this articlepermission to reproduce of this article or about obtaining reprintsInformation about obtaining registered trademark of AAAS. c 2005 by the American Association for the Advancement of Science; all rights reserved. The title SCIENCE is a CopyrightAmerican Association for the Advancement of Science, 1200 New York Avenue NW, Washington, DC 20005. Science (print ISSN 0036-8075; online ISSN 1095-9203) is published weekly, except the last week in December, by the on December 4, 2006 www.sciencemag.orgDownloaded fromtion for aspartic acid and attributed it tothe effect of hydrogen bonds present inthe crystal.Our diffraction experiment resultsdemonstrate that the combination of syn-chrotron primary radiation at a wave-length around l50.5 Å with a CCD areadetector can provide a high-precision dataset, suitable for accurate charge densitydetermination in a few hours. The resultsobtained are comparable or even superiorto those typically derivable from serialcounter data. The short acquisition timesopen new perspectives for the applicationof the method on larger molecules of bio-logical importance. 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Dittrich for preparing crystals suitable forthe experiment.14 October 1997; accepted 2 December 1997Space Geodetic Observations of Nazca–SouthAmerica Convergence Across the Central AndesEdmundo Norabuena, Lisa Leffler-Griffin, Ailin Mao,Timothy Dixon, Seth Stein,* I. Selwyn Sacks,Leonidas Ocola, Michael EllisSpace geodetic data recorded rates and directions of motion across the convergentboundary zone between the oceanic Nazca and continental South American plates inPeru and Bolivia. Roughly half of the overall convergence, about 30 to 40 millimeters peryear, accumulated on the locked plate interface and can be released in future earth-quakes. About 10 to 15 millimeters per year of crustal shortening occurred inland at
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