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Magee Jr., Charles W.; Danišík, Martin; Mernagh, Terry (2016)
Publisher: Copernicus Publications
Languages: English
Types: Article
Subjects: Geophysics. Cosmic physics, QC801-809
The current limitation in the accuracy and precision of inter-element analysis in secondary ion mass spectrometry (SIMS) is the ability to find measurable quantities that allow relative differences in ionization and transmission efficiency of secondary ions to be normalized. In uranium–thorium–lead geochronology, the ability to make these corrections, or "calibrate" the data, results in an accuracy limit of approximately 1 %. This study looks at the ionization of uranium and thorium oxide species, which are traditionally used in U–Pb calibration, to explore the conditions under which isotopologues, or molecular species whose composition differs only in the isotopic composition of one or more atoms in the molecule, remain in or deviate from equilibrium.

Isotopologue deficits of up to 0.2 (200 ‰) below ideal mixing are observed in UO2+ species during SIMS gechronological analyses using the SHRIMP IIe SIMS instrument. These are identified by bombarding natural U-bearing minerals with an 18O2 primary beam. The large anomalies are associated with repeat analyses down a single SIMS sputtering crater (Compston et al., 1984), analysis of high-uranium, radiation-damaged zircon, and analysis of baddeleyite. Analysis of zircon under routine conditions yield UO2+ isotopologue anomalies generally within a few percent of equilibrium. The conditions under which the isotopologue anomalies are observed are also conditions in which the UOx-based corrections, or calibration, for relative U vs. Pb ionization efficiencies fail. The existence of these isotopologue anomalies suggest that failure of the various UOx species to equilibrate with each other is the reason that none of them will successfully correct the U  / Pb ratio. No simple isotopologue-based correction is apparent. However, isotopologue disequilibrium appears to be a more sensitive tool for detecting high-U calibration breakdowns than Raman spectroscopy, which showed sharper peaks for  ∼  37 Ma high-uranium zircons than for reference zircons OG1 and Temora. U–Th–Sm / He ages were determined for aliquots of reference zircons OG1 (755±71 Ma) and Temora (323±43 Ma), suggesting that the broader Raman lines for the Temora reference zircons may be due to something other than accumulated radiation damage.

Isotopologue abundances for UO+ and ThO+ and their energy spectra are consistent with most or all molecular species being the product of atomic recombination when the primary beam impact energy is greater than 5.7 keV. This, in addition to the large UO2+ instrumentally generated isotopologue disequilibria, suggests that any attempts to use SIMS to detect naturally occurring isotopologue deviations could be tricky.
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    • Aleinikoff, J. N., Schenck, W. S., Plank, M. O., Srogi, L., Fanning, C. M., Kamo, S. L., and Bosbyshell, H.: Deciphering igneous and metamorphic events in high-grade rocks of the Wilmington Complex, Delaware: Morphology, cathodoluminescence and backscattered electron zoning, and SHRIMP U-Pb geochronology of zircon and monazite, Geol. Soc. Am. Bull., 118, 39-64, 2006.
    • Black, L. P., Kamo, S. L., Allen, C. M., Davis, D. W., Aleinikoff, J. N., Valley, J. W., Mundil, R., Campbell, I. H., Korsch, R. J., Williams, I. S., and Foudoulis, C.: Improved 206Pb/238U microprobe geochronology by the monitoring of a trace-elementrelated matrix effect; SHRIMP, ID-TIMS, ELA-ICP-MS and oxygen isotope documentation for a series of zircon standards, Chem. Geol., 205, 115-140, 2004.
    • Carson, C. J., Worden, K. E., Scrimgeour, I. R., and Stern, R. A.: The Palaeoproterozoic evolution of the Litchfield Province, western Pine Creek Orogen, northern Australia: Insight from SHRIMP U-Pb zircon and in situ monazite geochronology, Precambrian Res., 166, 145-167, 2008.
    • Chamberlain, K. J., Wilson, C. J. N., Wooden, J. L., Charlier, B. L. A., and Ireland, T. R.: New Perspectives on the Bishop Tuff from Zircon Textures, Ages and Trace Elements, J. Petrol., 55, 395-426, 2014.
    • Claoué-Long, J., Compston, W., Roberts, J., and Fanning, C. M.: Two Carboniferous ages: a comparison of SHRIMP zircon dating with conventional zircon ages and 40Ar/39Ar analysis, in: Geochronology Time Scales and Global Stratigraphic Correlation, edited by: Berggren, W. A., Kent, D. V., Aubrey, M. P., and Hardenbol, J., Society for Sedimentary Geology, SEPM Special Publication No. 54, 3-21, 1995.
    • Claoué-Long, J., Maidment, D., and Donnellan, N.: Stratigraphic timing constraints in the Davenport Province, central Australia: A basis for Palaeoproterozoic correlations, Precambrian Res., 166, 204-218, 2008.
    • Compston, W., Williams, I. S., and Meyer, C.: U-Pb geochronology of zircons from lunar breccia 73217 using a sensitive high massresolution ion microprobe, J. Geophys. Res., 89, B525-B534, 1984.
    • Danišík, M., Šteˇpancˇíková, P., and Evans, N. J.: Constraining long-term denudation and faulting history in intraplate regions by multisystem thermochronology: An example of the Sudetic Marginal Fault (Bohemian Massif, central Europe), Tectonics, 31, TC2003, https://doi.org/10.1029/2011TC003012, 2012.
    • Dawson, P., Hargreave, M. M., and Wilkinson, G. R.: The vibrational spectrum of zircon (ZrSiO4), J. Phys. C Solid State, 4, 240-256, 1971.
    • Farley, K. A., Wolf, R. A., and Silver, L. T.: The effects of long alpha-stopping distances on (U-Th)/He ages, Geochim. Cosmochim. Ac., 60, 4223-4229, 1996.
    • Fletcher, I. R., McNaughton, N. J., Davis, W. J., and Rasmussen, B.: Matrix effects and calibration limitations in ion probe U-Pb and Th-Pb dating of monazite, Chem. Geol., 270, 31-44, 2010.
    • Franzreb, K., Lörincˇík, J., and Williams, P.: Quantitative study of oxygen enhancement of sputtered ion yields. I. Argon ion bombardment of a silicon surface with O2 flood, Surf. Sci., 573, 291- 309, 2004.
    • Froude, D. O., Ireland, T. R., Kinny, P. D., Williams, I. S., Compston, W., Williams, I. R., and Myers, J. S.: Ion microprobe identification of 4100-4200 Myr-old terrestrial zircons, Nature, 304, 616-618, 1983.
    • Gregory, C. J., Rubatto, D., Allen, C. M., Williams, I. S., Hermann, J., and Ireland, T.: Allanite micro-geochronology: A LA-ICP-MS and SHRIMP U-Th-Pb study, Chem. Geol., 245, 162-182, 2007.
    • Guenthner, W. R., Reiners, P. W., Ketcham, R. A., Nasdala, L., and Giester, G.: Helium diffusion in natural zircon: Radiation damage, anisotropy, and the interpretation of zircon (U-Th)/He thermochronology, Am. J. Sci., 313, 145-198, 2013.
    • Ickert, R. B., Hiess, J., Williams, I. S., Holden, P., Ireland, T. R., Lanc, P., Schram, N., Foster, J. J., and Clement, S. W.: Determining high precision, in situ, oxygen isotope ratios with a SHRIMP II: Analyses of MPI-DING silicate-glass reference materials and zircon from contrasting granites, Chem. Geol., 257, 114-128, 2008.
    • Ickert, R. B., Mundil, R., Magee Jr., C. W., and Mulcahy, S. R.: The U-Th-Pb systematics of zircon from the Bishop Tuff: A case study in challenges to high-precision Pb/U geochronology at the millennial scale, Geochim. Cosmochim. Ac., 168, 88-110, 2015.
    • Ireland, T. R., Clement, S., Compston, W., Foster, J. J., Holden, P., Jenkins, B., Lanc, P., Schram, N., and Williams, I. S.:, Development of SHRIMP, Aust. J. Earth Sci., 55, 937-954, 2008.
    • Kilner, J. A., De Souza, R. A., and Fullarton, I. C.: Surface exchange of oxygen in mixed conducting perovskite oxides, Solid State Ionics, 86-88, 703-709, 1996.
    • Kostitsyn, Y. A., Volkov, V. N., and Zhuravlev, D. Z.: Trace elements and evolution of granite melt as exemplified by the Raumid Pluton, Southern Pamirs, Geochem. Int., 45, 971-982, 2007.
    • Laurie, J. R., Bodorkos, S., Nicoll, R. S., Crowley, J. L., Mantle, D. J., Mory, A. J., Wood, G. R., and Smith, T. E.: Calibrating the middle and late Permian palynostratigraphy of Australia to the geologic time-scale via U-Pb zircon CA-IDTIMS dating, Aust. J. Earth Sci., 63 701-730, 2016.
    • Ludwig, K.: SQUID 2: a user's manual, Berkeley Geochronology Center, Berkeley Geochronology Center Special Publication 5, 110 pp., 2010.
    • Magee, C., Ferris, J., and Magee, C.: Effect of impact energy on SIMS U-Pb zircon geochronology, Surf. Interface Anal., 46, 322-325, 2014.
    • Magee, C. W., Withnall, I. W., Hutton, L. J., Perkins, W. G., Donchak, P. J. T., Parsons, A., Blake, P. R., Sweet, I. P., and Carson, C. J.: Joint GSQ-GA geochronology project, Mount Isa Region, 2008-2009, Geological Survey of Queensland, 134 pp., 2012.
    • Manning, P. S., Sirman, J. D., De Souza, R. A., and Kilner, J. A.: The kinetics of oxygen transport in 9.5 mol % single crystal yttria stabilised zirconia, Solid State Ionics, 100, 1-10, 1997.
    • Matsuda, H.: Double focusing mass spectrometers of second order, International Journal of Mass Spectrometry and Ion Physics, 14, 219-233, 1974.
    • Nasdala, L., Irmer, G., and Wolf, D.: The degree of metamictization in zircon: a Raman spectroscopic study, Eur. J. Mineral., 7, 471- 478, 1995.
    • Nasdala, L., Wenzel, M., Vavra, G., Irmer, G., Wenzel, T., and Kober, B.: Metamictisation of natural zircon: accumulation versus thermal annealing of radioactivity-induced damage, Contrib. Mineral. Petr., 141, 125-144, 2004.
    • Pidgeon, R. T.: Zircon radiation damage ages, Chem. Geol., 367, 13-22, 2014.
    • Podor, R.: Raman spectra of the actinide-bearing monazites, Eur. J. Mineral., 7, 1353-1360, 1995.
    • Schaltegger, U., Schmitt, A. K., and Horstwood, M. S. A.: U-ThPb zircon geochronology by ID-TIMS, SIMS, and laser ablation ICP-MS: Recipes, interpretations, and opportunities, Chem. Geol., 402, 89-110, 2015.
    • Schmitt, A. K. and Zack, T.: High-sensitivity U-Pb rutile dating by secondary ion mass spectrometry (SIMS) with an O2C primary beam, Chem. Geol., 332-333, 65-73, 2012.
    • Schmitt, A. K., Chamberlain, K. R., Swapp, S. M., and Harrison, T. M.: In situ U-Pb dating of micro-baddeleyite by secondary ion mass spectrometry, Chem. Geol., 269, 386-395, 2010.
    • Schuhmacher, M., de Chambost, E., McKeegan, K. D., Harrison, T. M., and Migeon, H.: In situ dating of zircon with the CAMECA ims 1270, edited by: Benninghoven, A., Secondary Ion Mass Spectrometry, SIMS IX, 919-922, 1994.
    • Sobers Jr., R. C., Franzreb, K., and Williams, P.: Quantitative measurement of O = Si ratios in oxygen-sputtered silicon using 18O implant standards, Appl. Surf. Sci., 231-232, 729-733, 2004.
    • Stern, R. A. and Amelin, Y.: Assessment of errors in SIMS zircon U-Pb geochronology using a natural zircon standard and NIST SRM 610 glass, Chem. Geol., 197, 111-142, 2003.
    • Stern, R. A. and Berman, R. G.: Monazite U-Pb and Th-Pb geochronology by ion microprobe, with an application to in situ dating of an Archean metasedimentary rock, Chem. Geol., 172, 113-130, 2001.
    • Stern, R. A., Bodorkos, S., Kamo, S. L., Hickman, A. H., and Corfu, F.: Measurement of SIMS Instrumental Mass Fractionation of Pb Isotopes During Zircon Dating, Geostand. Geoanal. Res., 33, 145-168, 2009.
    • Taylor, R., Clark, C., and Reddy, S. M.: The effect of grain orientation on secondary ion mass spectrometry (SIMS) analysis of rutile, Chem. Geol., 300-301, 81-87, 2012.
    • Weber, W. J., Ewing, R. C., and Meldrum, A.: The kinetics of alphadecay-induced amorphization in zircon and apatite containing weapons-grade plutonium or other actinides, J. Nucl. Mater., 250, 147-155, 1997.
    • White, L. T. and Ireland, T. R.: High-uranium matrix effect in zircon and its implications for SHRIMP U-Pb age determinations, Chem. Geol., 306-307, 78-91, 2012.
    • Williams, I. S.: U-Th-Pb Geochronology by Ion Microprobe, in: Applications of microanalytical techniques to understanding mineralizing processes, edited by: McKibben, M. A., Shanks III, W. C., and Ridley, W. I., Rev. Econ. Geol., 7, 1-35, 1998.
    • Williams, I. S. and Hergt, J.: U-Pb dating of Tasmanian dolerites: a cautionary tale of SHRIMP analysis of high-U zircon, in: Beyond 2000: New Frontiers in Isotope Geoscience, Lorne, edited by: Woodhead, J. D., Hergt, J. M., and Noble, W. P., 185-188, 2000.
    • Wingate, M. T. D. and Compston, W.: Crystal orientation effects during ion microprobe U-Pb analysis of baddeleyite, Chem. Geol., 168, 75-97, 2000.
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