Manioc : Portail | resultats 1 - 20 pour la recherche: Chapman and Hall

Éditeur(s) : HAL CCSD Elsevier
Résumé : Handheld energy dispersive portable X-ray spectrometers (pXRF) are generally designed and used for qualitative survey applications. We developed shipboard quantitative analysis protocols for pXRF and employed the instrument to make over 2000 individual abundance measurements for a selection of major and trace elements on over 1200 m of recovered core during the eight weeks of the International Ocean Discovery Program (IODP) Expedition 352 to the Izu-Bonin forearc. pXRF analytical performance, accuracy and precision were found to be the same on powdered rock samples and on freshly cut rock surfaces, and sample results were similar within error to measurements made via shipboard ICP-OES analysis save at low abundance levels for a few elements. Instrument performance was optimal for elements between Z = 19 and Z = 40, and the system yielded reproducible data for K, Ca, Ti, V, Cr, Mn, Fe, Cu, Zn, Rb, Sr, and Zr on both powdered samples and rock surfaces. Working curves developed via pXRF measurement of a suite of geologic standard reference materials and well-characterized lavas permitted accurate quantitative measurements for many of the examined elements on both sample powders and rock surfaces. Although pXRF has been sporadically employed on previous cruises, Expedition 352 is the first time a detailed, high-density chemostratigraphy of recovered core samples was collected using pXRF measurements of rock core surfaces. These high-resolution data allowed the recognition of chemically distinct eruptive units in near real-time. The rapid identification of geochemical trends vastly improved our selection of samples for shipboard and shore-based analysis, permitted a more comprehensive interpretation of our Expedition results, and provided key decision-making information for drilling operations.
ISSN: 0009-2541

hal-01553188
https://hal.archives-ouvertes.fr/hal-01553188
DOI : 10.1016/j.chemgeo.2017.01.007

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Subduction initiation and ophiolite crust: new insights from IODP drilling
Auteur(s) : Reagan, Mark K. Pearce, Julian a. Petronotis, Katerina Almeev, Renat R. Avery, Aaron j. Carvallo, C. Chapman, Timothy Christeson, Gail l.
Auteurs secondaires : University of Iowa [Iowa] Cardiff University A&M University, College Station Institut fur Mineralogy, Hannovre Florida State University Institut de minéralogie, de physique des matériaux et de cosmochimie (IMPMC) ; Muséum National d'Histoire Naturelle (MNHN) - Université Pierre et Marie Curie - Paris 6 (UPMC) - Institut de recherche pour le développement [IRD] : UR206 - Centre National de la Recherche Scientifique (CNRS) University of Sydney University of Texas

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Mémoires sur le contact des races : communiqués au premier Congrès universel des races tenu à l'Université de Londres du 26 au 29 juillet 1911
Auteur(s) : Universal races congress
Auteurs secondaires : Spiller, Gustav (1864-1940). Éditeur scientifique
Année de publication :

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Flora brasiliensis : enumeratio plantarum in Brasilia hactenus detectarum quas suis aliorumque botanicorum studiis descriptas et methodo naturali digestas partim icone illustratas. Volumen XIII, Pars III
Auteur(s) : Bennett, Alfred William (1833-1902) Urban, Ignaz (1848-1931) Solms-Laubach, Hermann zu (1842-1915) Radlkofer, Ludwig (1829-1927)
Auteurs secondaires : Martius, Karl Friedrich Philipp von (1794-1868) Eichler, August Wilhelm (1837-1887)
Année de publication :

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