Assessment of Different Digestion Procedures for Mo Isotope Measurements of Black and Grey Shales Using the Double Spike Technique

Jin Li; Xiangkun Zhu; Suohan Tang

doi:10.1007/s12583-021-1520-1

Volume 33 Issue 1

Feb 2022

Turn off MathJax

Article Contents

Journal of Earth Science > 2022 > 33(1): 76-81.

Jin Li, Xiangkun Zhu, Suohan Tang. Assessment of Different Digestion Procedures for Mo Isotope Measurements of Black and Grey Shales Using the Double Spike Technique. Journal of Earth Science, 2022, 33(1): 76-81. doi: 10.1007/s12583-021-1520-1

Citation:

Jin Li, Xiangkun Zhu, Suohan Tang. Assessment of Different Digestion Procedures for Mo Isotope Measurements of Black and Grey Shales Using the Double Spike Technique. Journal of Earth Science, 2022, 33(1): 76-81. doi: 10.1007/s12583-021-1520-1

Citation:

PDF( 432 KB)

Assessment of Different Digestion Procedures for Mo Isotope Measurements of Black and Grey Shales Using the Double Spike Technique

doi: 10.1007/s12583-021-1520-1

MNR Key Laboratory of Isotope Geology, MNR Key Laboratory of Deep-Earth Dynamics, Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037, China

More Information

Corresponding author: Xiangkun Zhu, xiangkun@cags.ac.cn
Received Date: 02 Feb 2021
Accepted Date: 26 Jul 2021
Publish Date: 28 Feb 2022

Abstract

Abstract

This study investigates the behavior of Mo and Mo isotopes (δ⁹⁸Mo) in shales following leaching with HCl and HNO₃ with the aim of simplifying the shale dissolution procedure. Up to 6% of the Mo was lost and the Mo isotopes were unaffected when shales were leached using 9 M HCl after ashing. Bulk sample digestion or leaching by 4 M or more concentrated HCl after ashing were all found to be acceptable and reliable approaches to the analysis of Mo isotopes in shales. After black shale (CAGS-BS) was leached with 2 M HCl, 1 M HCl, and 9 M HNO₃, the Mo concentration ([Mo]) in the leachate was lower and δ⁹⁸Mo was heavier than that obtained from bulk digestion. A Mo isotope mass-balance model showed that the δ⁹⁸Mo in the residues was lighter than the δ⁹⁸Mo from the bulk digestion of CAGS-BS and of crustal igneous rocks. No more Mo was lost, nor did Mo isotope fractionation, if the double spike was added before rather than after ashing and followed by bulk digestion or leaching with 9 M HCl. For efficiency, leaching using 4 M or more concentrated HCl after ashing is preferred for Mo isotope measurements.
- Mo isotopes,
- double spike,
- ashing,
- bulk digestion,
- leaching

FullText(HTML)

References(31)

References

Algeo, T. J., Maynard, J. B., 2004. Trace-Element Behavior and Redox Facies in Core Shales of Upper Pennsylvanian Kansas-Type Cyclothems. Chemical Geology, 206(3/4): 289-318. https://doi.org/10.1016/j.chemgeo.2003.12.009

Barling, J., Arnold, G. L., Anbar, A. D., 2001. Natural Mass-Dependent Variations in the Isotopic Composition of Molybdenum. Earth and Planetary Science Letters, 193(3/4): 447-457. https://doi.org/10.1016/S0012-821x(01)00514-3

Dahl, T. W., Ruhl, M., Hammarlund, E. U., et al., 2013. Tracing Euxinia by Molybdenum Concentrations in Sediments Using Handheld X-Ray Fluorescence Spectroscopy (HHXRF). Chemical Geology, 360/361: 241-251. https://doi.org/10.1016/j.chemgeo.2013.10.022

Dahl, T. W., Wirth, S. B., 2017. Molybdenum Isotope Fractionation and Speciation in a Euxinic Lake—Testing Ways to Discern Isotope Fractionation Processes in a Sulfidic Setting. Chemical Geology, 460: 84-92. https://doi.org/10.1016/j.chemgeo.2017.04.018

Dickson, A. J., Idiz, E., Porcelli, D., et al., 2020. The Influence of Thermal Maturity on the Stable Isotope Compositions and Concentrations of Molybdenum, Zinc and Cadmium in Organic-Rich Marine Mudrocks. Geochimica et Cosmochimica Acta, 287: 205-220. https://doi.org/10.1016/j.gca.2019.11.001

Gaspers, N., Magna, T., Ackerman, L., 2020. Molybdenum Mass Fractions and Stable Isotope Compositions of Sedimentary Carbonate and Silicate Reference Materials. Geostandards and Geoanalytical Research, 44(2): 363-374. https://doi.org/10.1111/ggr.12314

Goldberg, T., Archer, C., Vance, D., et al., 2009. Mo Isotope Fractionation during Adsorption to Fe(Oxyhydr) Oxides. Geochimica et Cosmochimica Acta, 73(21): 6502-6516. https://doi.org/10.1016/j.gca.2009.08.004

Goldberg, T., Gordon, G., Izon, G., et al., 2013. Resolution of Inter-Laboratory Discrepancies in Mo Isotope Data: An Intercalibration. Journal of Analytical Atomic Spectrometry, 28(5): 724-735. https://doi.org/10.1039/c3ja30375f

Gordon, G. W., Lyons, T. W., Arnold, G. L., et al., 2009. When do Black Shales Tell Molybdenum Isotope Tales?. Geology, 37(6): 535-538. https://doi.org/10.1130/g25186a.1

Helz, G. R., Miller, C. V., Charnock, J. M., et al., 1996. Mechanism of Molybdenum Removal from the Sea and Its Concentration in Black Shales: EXAFS Evidence. Geochimica et Cosmochimica Acta, 60(19): 3631-3642. https://doi.org/10.1016/0016-7037(96)00195-0

Herrmann, A. D., Kendall, B., Algeo, T. J., et al., 2012. Anomalous Molybdenum Isotope Trends in Upper Pennsylvanian Euxinic Facies: Significance for Use of δ⁹⁸Mo as a Global Marine Redox Proxy. Chemical Geology, 324/325: 87-98. https://doi.org/10.1016/j.chemgeo.2012.05.013

Kendall, B., Creaser, R. A., Gordon, G. W., et al., 2009. Re-Os and Mo Isotope Systematics of Black Shales from the Middle Proterozoic Velkerri and Wollogorang Formations, McArthur Basin, Northern Australia. Geochimica et Cosmochimica Acta, 73(9): 2534-2558. https://doi.org/10.1016/j.gca.2009.02.013

Kurzweil, F., Wille, M., Schoenberg, R., et al., 2015. Continuously Increasing δ⁹⁸Mo Values in Neoarchean Black Shales and Iron Formations from the Hamersley Basin. Geochimica et Cosmochimica Acta, 164: 523-542. https://doi.org/10.1016/j.gca.2015.05.009

Li, J., Zhu, X. K., Tang, S. H., et al., 2016. High-Precision Measurement of Molybdenum Isotopic Compositions of Selected Geochemical Reference Materials. Geostandards and Geoanalytical Research, 40(3): 405-415. https://doi.org/10.1111/j.1751-908x.2015.00369.x

Liermann, L. J., Mathur, R., Wasylenki, L. E., et al., 2011. Extent and Isotopic Composition of Fe and Mo Release from Two Pennsylvania Shales in the Presence of Organic Ligands and Bacteria. Chemical Geology, 281(3/4): 167-180. https://doi.org/10.1016/j.chemgeo. 2010.12.005 doi: 10.1016/j.chemgeo.2010.12.005

Malinovsky, D., Rodushkin, I., Baxter, D. C., et al., 2005. Molybdenum Isotope Ratio Measurements on Geological Samples by MC-ICPMS. International Journal of Mass Spectrometry, 245(1/2/3): 94-107. https://doi.org/10.1016/j.ijms.2005.07.007

McLennan, S. M., 2001. Relationships between the Trace Element Composition of Sedimentary Rocks and Upper Continental Crust. Geochemistry, Geophysics, Geosystems, 2(4): e2000gc000109. https://doi.org/10.1029/2000gc000109

Nägler, T. F., Anbar, A. D., Archer, C., et al., 2014. Proposal for an International Molybdenum Isotope Measurement Standard and Data Representation. Geostandards and Geoanalytical Research, 38(2): 149-151. https://doi.org/10.1111/j.1751-908x.2013.00275.x

Nägler, T. F., Neubert, N., Böttcher, M. E., et al., 2011. Molybdenum Isotope Fractionation in Pelagic Euxinia: Evidence from the Modern Black and Baltic Seas. Chemical Geology, 289(1/2): 1-11. https://doi.org/10.1016/j.chemgeo.2011.07.001

Nägler, T. F., Siebert, C., Lüschen, H., et al., 2005. Sedimentary Mo Isotope Record across the Holocene Fresh-Brackish Water Transition of the Black Sea. Chemical Geology, 219(1/2/3/4): 283-295. https://doi.org/10.1016/j.chemgeo.2005.03.006

Neubert, N., Nägler, T. F., Böttcher, M. E., 2008. Sulfidity Controls Molybdenum Isotope Fractionation into Euxinic Sediments: Evidence from the Modern Black Sea. Geology, 36(10): 775-778. https://doi.org/10.1130/g24959a.1

Ostrander, C. M., Sahoo, S. K., Kendall, B., et al., 2019. Multiple Negative Molybdenum Isotope Excursions in the Doushantuo Formation (South China) Fingerprint Complex Redox-Related Processes in the Ediacaran Nanhua Basin. Geochimica et Cosmochimica Acta, 261: 191-209. https://doi.org/10.1016/j.gca.2019.07.016

Pearce, C. R., Cohen, A. S., Parkinson, I. J., 2009. Quantitative Separation of Molybdenum and Rhenium from Geological Materials for Isotopic Determination by MC-ICP-MS. Geostandards and Geoanalytical Research, 33(2): 219-229. https://doi.org/10.1111/j.1751-908x.2009.00012.x

Rudge, J. F., Reynolds, B. C., Bourdon, B., 2009. The Double Spike Toolbox. Chemical Geology, 265(3/4): 420-431. https://doi.org/10.1016/j.chemgeo.2009.05.010

Scott, C., Lyons, T. W., 2012. Contrasting Molybdenum Cycling and Isotopic Properties in Euxinic versus Non-Euxinic Sediments and Sedimentary Rocks: Refining the Paleoproxies. Chemical Geology, 324/325: 19-27. https://doi.org/10.1016/j.chemgeo.2012.05.012

Scott, C., Lyons, T. W., Bekker, A., et al., 2008. Tracing the Stepwise Oxygenation of the Proterozoic Ocean. Nature, 452(7186): 456-459. https://doi.org/10.1038/nature06811

Siebert, C., Nägler, T. F., von Blanckenburg, F., et al., 2003. Molybdenum Isotope Records as a Potential New Proxy for Paleoceanography. Earth and Planetary Science Letters, 211(1/2): 159-171. https://doi.org/10.1016/s0012-821x(03)00189-4

Voegelin, A. R., Nägler, T. F., Pettke, T., et al., 2012. The Impact of Igneous Bedrock Weathering on the Mo Isotopic Composition of Stream Waters: Natural Samples and Laboratory Experiments. Geochimica et Cosmochimica Acta, 86: 150-165. https://doi.org/10.1016/j.gca.2012.02.029

Wang, Z. C., Becker, H., Wombacher, F., 2015. Mass Fractions of S, Cu, Se, Mo, Ag, Cd, In, Te, Ba, Sm, W, Tl and Bi in Geological Reference Materials and Selected Carbonaceous Chondrites Determined by Isotope Dilution ICP-MS. Geostandards and Geoanalytical Research, 39(2): 185-208. https://doi.org/10.1111/j.1751-908x.2014.00312.x

Zhao, P. P., Li, J., Zhang, L., et al., 2016. Molybdenum Mass Fractions and Isotopic Compositions of International Geological Reference Materials. Geostandards and Geoanalytical Research, 40(2): 217-226. https://doi.org/10.1111/j.1751-908x.2015.00373.x

Zhou, L., Zhou, H. -B., Li M., et al., 2007. Molybdenum Isotope Signatures from Yangtze Craton Continental Margin and Its Indication to Organic Burial Rate. Earth Science, 16(6): 759-766 (in Chinese with English Abstract) http://d.wanfangdata.com.cn/Periodical_zggdxxxswz-dqkx200704005.aspx

Relative Articles

Supplements(0)

Cited By

Proportional views

Proportional views

通讯作者: 陈斌, bchen63@163.com

1.
沈阳化工大学材料科学与工程学院沈阳 110142

Tables(4)

Get Citation

PDF

XML

Article Metrics

Article views(792) PDF downloads(73)

Assessment of Different Digestion Procedures for Mo Isotope Measurements of Black and Grey Shales Using the Double Spike Technique

doi: 10.1007/s12583-021-1520-1

Abstract

References

Proportional views

Catalog

通讯作者: 陈斌, bchen63@163.com

Article Metrics

Proportional views

Related

Export File

Citation

Format

Content