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Chemical U-Th-Pb dating of monazite by 3D-Micro x-ray fluorescence analysis with synchrotron radiation

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Standard

Chemical U-Th-Pb dating of monazite by 3D-Micro x-ray fluorescence analysis with synchrotron radiation. / Schmitz, Susanne; Möller, Andreas; Wilke, Max; Malzer, Wolfgang; Kanngiesser, Birgit; Bousquet, Romain; Berger, Alfons; Schefer, Seneca.

I: European Journal of Mineralogy, Bind 21, Nr. 5, 2009, s. 927–945.

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningfagfællebedømt

Harvard

Schmitz, S, Möller, A, Wilke, M, Malzer, W, Kanngiesser, B, Bousquet, R, Berger, A & Schefer, S 2009, 'Chemical U-Th-Pb dating of monazite by 3D-Micro x-ray fluorescence analysis with synchrotron radiation', European Journal of Mineralogy, bind 21, nr. 5, s. 927–945. https://doi.org/10.1127/0935-1221/2009/0021-1964

APA

Schmitz, S., Möller, A., Wilke, M., Malzer, W., Kanngiesser, B., Bousquet, R., ... Schefer, S. (2009). Chemical U-Th-Pb dating of monazite by 3D-Micro x-ray fluorescence analysis with synchrotron radiation. European Journal of Mineralogy, 21(5), 927–945. https://doi.org/10.1127/0935-1221/2009/0021-1964

Vancouver

Schmitz S, Möller A, Wilke M, Malzer W, Kanngiesser B, Bousquet R o.a. Chemical U-Th-Pb dating of monazite by 3D-Micro x-ray fluorescence analysis with synchrotron radiation. European Journal of Mineralogy. 2009;21(5):927–945. https://doi.org/10.1127/0935-1221/2009/0021-1964

Author

Schmitz, Susanne ; Möller, Andreas ; Wilke, Max ; Malzer, Wolfgang ; Kanngiesser, Birgit ; Bousquet, Romain ; Berger, Alfons ; Schefer, Seneca. / Chemical U-Th-Pb dating of monazite by 3D-Micro x-ray fluorescence analysis with synchrotron radiation. I: European Journal of Mineralogy. 2009 ; Bind 21, Nr. 5. s. 927–945.

Bibtex

@article{f59292f080c511de8bc9000ea68e967b,
title = "Chemical U-Th-Pb dating of monazite by 3D-Micro x-ray fluorescence analysis with synchrotron radiation",
abstract = "A confocal set-up for three-dimensional (3D) micro X-ray fluorescence (micro-XRF) was used at the mySpot beamline at BESSY II, which allows compositional depth profiling for various applications. We present results obtained with a confocal 3D micro-XRF set-up for chemical age dating using the U, Th and Pb concentrations of monazite within rock thin sections. The probing volume was determined to be approximately 21 × 21 × 24 µm3 for W-La using an excitation energy of 19 keV. The relative detection limits particularly for Pb are below 10 ppm (for counting times of 1000 s). Therefore, this 3D micro-XRF set-up is suitable for dating of minerals with low Pb concentrations as long as all Pb is radiogenic, allowing spatial resolution comparable to ion microprobe or laser ablation techniques. The set-up was tested on monazites that are well characterized by isotopic techniques and have a wide range of ages, varying from 20 Ma to 1.82 Ga. Reference materials (GM3, F6, 3345) can be reproduced within error. The spread in the ages of all points determined by 3D micro-XRF is within 8 {\%} of the isotopic reference value. The average 3D micro-XRF dates reproduce the reference ages with discrepancies between 10 and 13 Ma which translate to deviations of 1-4 {\%}. Younger monazite samples from the European Alps (Baceno2, Bi9801) show slightly older 3D micro-XRF dates than those determined by isotopic techniques and table-top micro-XRF on whole grains. We interpret this to be related to age heterogeneities smaller than the spatial resolution and/or contributions by common Pb, which is a limitation for this technique. The method was then applied to monazites of unknown age from sapphirine-bearing granulites originating from the Gruf Complex (Alps, N-Italy). The 3D micro-XRF mean date was determined as 33 ± 4.4 Ma (2s) and was verified by ID-TIMS techniques. This age can be reliably interpreted as the age of the high-temperature (HT) event because the monazites are included in and intergrown with HT minerals (sapphirine, high-Al orthopyroxene)",
keywords = "Faculty of Science, gruf complex, synchrotron radiation, confocal, flourescence analysis, chemical dating, monazite, 3D-micro x-ray",
author = "Susanne Schmitz and Andreas M{\"o}ller and Max Wilke and Wolfgang Malzer and Birgit Kanngiesser and Romain Bousquet and Alfons Berger and Seneca Schefer",
year = "2009",
doi = "10.1127/0935-1221/2009/0021-1964",
language = "English",
volume = "21",
pages = "927–945",
journal = "European Journal of Mineralogy",
issn = "0935-1221",
publisher = "E.Schweizerbart'sche Verlagsbuchhandlung",
number = "5",

}

RIS

TY - JOUR

T1 - Chemical U-Th-Pb dating of monazite by 3D-Micro x-ray fluorescence analysis with synchrotron radiation

AU - Schmitz, Susanne

AU - Möller, Andreas

AU - Wilke, Max

AU - Malzer, Wolfgang

AU - Kanngiesser, Birgit

AU - Bousquet, Romain

AU - Berger, Alfons

AU - Schefer, Seneca

PY - 2009

Y1 - 2009

N2 - A confocal set-up for three-dimensional (3D) micro X-ray fluorescence (micro-XRF) was used at the mySpot beamline at BESSY II, which allows compositional depth profiling for various applications. We present results obtained with a confocal 3D micro-XRF set-up for chemical age dating using the U, Th and Pb concentrations of monazite within rock thin sections. The probing volume was determined to be approximately 21 × 21 × 24 µm3 for W-La using an excitation energy of 19 keV. The relative detection limits particularly for Pb are below 10 ppm (for counting times of 1000 s). Therefore, this 3D micro-XRF set-up is suitable for dating of minerals with low Pb concentrations as long as all Pb is radiogenic, allowing spatial resolution comparable to ion microprobe or laser ablation techniques. The set-up was tested on monazites that are well characterized by isotopic techniques and have a wide range of ages, varying from 20 Ma to 1.82 Ga. Reference materials (GM3, F6, 3345) can be reproduced within error. The spread in the ages of all points determined by 3D micro-XRF is within 8 % of the isotopic reference value. The average 3D micro-XRF dates reproduce the reference ages with discrepancies between 10 and 13 Ma which translate to deviations of 1-4 %. Younger monazite samples from the European Alps (Baceno2, Bi9801) show slightly older 3D micro-XRF dates than those determined by isotopic techniques and table-top micro-XRF on whole grains. We interpret this to be related to age heterogeneities smaller than the spatial resolution and/or contributions by common Pb, which is a limitation for this technique. The method was then applied to monazites of unknown age from sapphirine-bearing granulites originating from the Gruf Complex (Alps, N-Italy). The 3D micro-XRF mean date was determined as 33 ± 4.4 Ma (2s) and was verified by ID-TIMS techniques. This age can be reliably interpreted as the age of the high-temperature (HT) event because the monazites are included in and intergrown with HT minerals (sapphirine, high-Al orthopyroxene)

AB - A confocal set-up for three-dimensional (3D) micro X-ray fluorescence (micro-XRF) was used at the mySpot beamline at BESSY II, which allows compositional depth profiling for various applications. We present results obtained with a confocal 3D micro-XRF set-up for chemical age dating using the U, Th and Pb concentrations of monazite within rock thin sections. The probing volume was determined to be approximately 21 × 21 × 24 µm3 for W-La using an excitation energy of 19 keV. The relative detection limits particularly for Pb are below 10 ppm (for counting times of 1000 s). Therefore, this 3D micro-XRF set-up is suitable for dating of minerals with low Pb concentrations as long as all Pb is radiogenic, allowing spatial resolution comparable to ion microprobe or laser ablation techniques. The set-up was tested on monazites that are well characterized by isotopic techniques and have a wide range of ages, varying from 20 Ma to 1.82 Ga. Reference materials (GM3, F6, 3345) can be reproduced within error. The spread in the ages of all points determined by 3D micro-XRF is within 8 % of the isotopic reference value. The average 3D micro-XRF dates reproduce the reference ages with discrepancies between 10 and 13 Ma which translate to deviations of 1-4 %. Younger monazite samples from the European Alps (Baceno2, Bi9801) show slightly older 3D micro-XRF dates than those determined by isotopic techniques and table-top micro-XRF on whole grains. We interpret this to be related to age heterogeneities smaller than the spatial resolution and/or contributions by common Pb, which is a limitation for this technique. The method was then applied to monazites of unknown age from sapphirine-bearing granulites originating from the Gruf Complex (Alps, N-Italy). The 3D micro-XRF mean date was determined as 33 ± 4.4 Ma (2s) and was verified by ID-TIMS techniques. This age can be reliably interpreted as the age of the high-temperature (HT) event because the monazites are included in and intergrown with HT minerals (sapphirine, high-Al orthopyroxene)

KW - Faculty of Science

KW - gruf complex

KW - synchrotron radiation

KW - confocal

KW - flourescence analysis

KW - chemical dating

KW - monazite

KW - 3D-micro x-ray

U2 - 10.1127/0935-1221/2009/0021-1964

DO - 10.1127/0935-1221/2009/0021-1964

M3 - Journal article

VL - 21

SP - 927

EP - 945

JO - European Journal of Mineralogy

JF - European Journal of Mineralogy

SN - 0935-1221

IS - 5

ER -

ID: 13547613