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Licensed Unlicensed Requires Authentication Published by De Gruyter November 30, 2017

Age discordance and mineralogy

Igor M. Villa and John M. Hanchar
From the journal American Mineralogist

Abstract

Observations of discordant ages, meaning that an age given by one mineral geochronometer is different from the age given by another geochronometer from the same rock, began in the early days of geochronology. In the late 1950s and 1960s, discordant U-Pb zircon ages were unquestioningly attributed to Pb diffusion at high temperature. Later, the mineralogical properties and the petrogenesis of the zircon crystals being dated was recognized as a key factor in obtaining concordant U-Pb ages. Advances in analytical methods allowed the analysis of smaller and smaller zircon multigrain fractions, then the analysis of individual grains, and even pieces of grains, with higher degrees of concordancy. Further advances allowed a higher analytical precision, a clearer perception of accuracy, and a better statistical resolution of age discordance. As for understanding the cause(s) of discordance, belief revision followed the coupling of imaging, cathodoluminescence (CL), and backscattered electrons (BSE), to in situ dating by secondary ion mass spectrometry (SIMS) or by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). Discordant zircon and other accessory minerals (e.g., monazite, apatite, etc.) often consist of young rims accreted onto/into older cores. Age gradients are sharp, and no Pb diffusion gradients are observed. As U-Pb discordance in crystalline, non-radiation damaged grains is caused by diachronous, heterochemical mineral generations, interpretations of mineral ages, based on the exclusive role of diffusion, are superseded, and closure temperatures of zircon and monazite are irrelevant in geological reality.

Other isotopic systems (Rb-Sr, K-Ar) were believed, since the 1960s, to be similarly controlled by the diffusivity of radiogenic daughters. When zircon and monazite discordance were recognized as zone accretion/reaction with sharp boundaries that showed little or no high-temperature diffusive re-equilibration, the other chronometric systems were left behind, and interpretations of mineral ages based on the exclusive role of diffusion survived.

The evidence from textural-petrologic imaging (CL, BSE) and element mapping by electron probe microanalyzer (EPMA) or high spatial resolution SIMS or LA-ICP-MS provides the decisive constraints. All microcline and mica geochronometers that have been characterized in detail document patchy textures and evidence for mineral replacement reactions. It is important not to confuse causes and effects; heterochemical microstructures are not the cause of Ar and Sr loss; rather, they follow it. Ar and Sr loss by dissolution of the older mineral generation occurs first, heterochemical textures form later, when the replacive assemblage recrystallizes. Heterochemical mineral generations are identified and dated by their Ca/Cl/K systematics in 39Ar-40Ar. Replacive reactions adding or removing Cl, such as, e.g., sericite overgrowths on K-feldspar, retrograde muscovite intergrowths with phengite, etc. are detected by Cl/K vs. Ar/K isotope correlation diagrams. Ca-poor reaction products, such as, e.g., young biotite intergrown with older amphibole, adularia replacing microcline, etc., can be easily identified by Ca/K vs. Ar/K diagrams supported by EPMA analyses. Mixed mineral generations are observed to be the cause of discordant, staircase-shaped age spectra, while step-heating of crystals with age gradients produces concordant plateaus. Age gradients are therefore unrelated to staircase age spectra.

There is a profound analogy between the U-Pb, Rb-Sr, and K-Ar systems. Pb and Ar diffusion rates are both much slower than mineral replacement rates for all T < 750 °C. Patchy retrogression textures are always associated with heterochemical signatures (U/Th ratios, REE patterns, Ca/Cl/K ratios). As a rule, single-generation minerals with low amounts of radiation damage give concordant ages, whereas discordance is caused by mixtures of heterochemical, resolvably diachronous, mineral generations in petrologic disequilibrium. This can also include (sub-)grains that have accumulated significant amounts of radiation damage. For accurate geochronology the petrologic characterization with the appropriate technique(s) of the minerals to be dated, and the petrologic context at large, are as essential as the mass spectrometric analyses.

Acknowledgments

Detailed reviews by D.E. Harlov, A.R. Heri, and two anonymous reviewers helped clarify many descriptions of actual observations. A. Berger is thanked for contributing to sample Ga142 presented in Figure 9. Thanks to G. Dunning for many fruitful discussion on U-Pb geochronology and to M.J. Whitehouse for doing the SIMS analyses presented in Figure 3.

References cited

Arnaud, N.O., and Eide, E.A. (2000) Brecciation-related argon redistribution in alkali feldspars: An in naturo crushing study. Geochimica et Cosmochimica Acta, 64, 3201–3215.10.1016/S0016-7037(00)00411-7Search in Google Scholar

Berger, A., Wehrens, P., Lanari, P., Zwingmann, H., and Herwegh, M. (2017) Microstructures, mineral chemistry and geochronology of white micas along a retrograde evolution: An example from the Aar massif (Central Alps, Switzerland). Tectonophysics, 721, 179–195.10.1016/j.tecto.2017.09.019Search in Google Scholar

Bingen, B., and van Breemen, O. (1998) U-Pb monazite ages in amphibolite- to granulite-facies orthogneiss reflect hydrous mineral breakdown reactions: Sveconorwegian Province of SW Norway. Contributions to Mineralogy and Petrology, 132, 336–353.10.1007/s004100050428Search in Google Scholar

Bracciali, L., Parrish, R.R., Horstwood, M.S.A., Condon, D.J., and Najman, Y. (2013) U–Pb LA-(MC)-ICP-MS dating of rutile: new reference materials and applications to sedimentary provenance. Chemical Geology, 347, 82–101.10.1016/j.chemgeo.2013.03.013Search in Google Scholar

Chafe, A.N., Villa, I.M., Hanchar, J.M., and Wirth, R. (2014) A re-examination of petrogenesis and 40Ar/39Ar systematics in the the Chain of Ponds K-feldspar: “diffusion domain” archetype versus polyphase hygrochronology. Contributions to Mineralogy and Petrology, 167(5), 1010.10.1007/s00410-014-1010-xSearch in Google Scholar

Cherniak, D.J. (1993) Lead diffusion in titanite and preliminary results on the effects of radiation damage on Pb transport. Chemical Geology, 110, 177–194.10.1016/0009-2541(93)90253-FSearch in Google Scholar

Cherniak, D.J. (2000) Pb diffusion in rutile. Contributions to Mineralogy and Petrology, 139, 198–207.10.1007/PL00007671Search in Google Scholar

Cherniak, D.J. (2010) Diffusion in accessory minerals: zircon, titanite, apatite, monazite and xenotime. In Y. Zhang and D.J. Cherniak, Eds., Diffusion in Minerals and Melts. Reviews in Mineralogy & Geochemistry, 72, 827–869.10.1515/9781501508394-019Search in Google Scholar

Cherniak, D.J., and Watson, E.B. (2000) Pb diffusion in zircon. Chemical Geology, 172, 5–24.10.1016/S0009-2541(00)00233-3Search in Google Scholar

Cherniak, D.J., Lanford, W.A., and Ryerson, F.J. (1991) Lead diffusion in apatite and zircon using ion implantation and Rutherford backscattering techniques. Geochimica et Cosmochimica Acta, 55, 1663–1673.10.1016/0016-7037(91)90137-TSearch in Google Scholar

Chew, D.M., Petrus, J.A., Kenny, G.G., and McEvoy, N. (2017) Rapid high-resolution U–Pb LA-Q-ICP-MS age mapping of zircon. Journal of Analytical Atomic Spectrometry, 32, 262–276.10.1039/C6JA00404KSearch in Google Scholar

Cocherie, A., Legendre, O., Peucat, J.J., and Kouamelan, A.N. (1998) Geochronology of polygenetic monazites constrained by in situ electron microprobe Th-U-total lead determination: Implications for lead behaviour in monazite. Geochimica et Cosmochimica Acta, 62, 2475–2497.10.1016/S0016-7037(98)00171-9Search in Google Scholar

Corfu, F. (2013) A century of U-Pb geochronology: The long quest towards concordance. Geological Society of America Bulletin, 125, 33–47, 10.1130/B30698.1.Search in Google Scholar

Corfu, F., and Stone, D. (1998) The significance of titanite and apatite U-Pb ages: Constraints for the post-magmatic thermal-hydrothermal evolution of a batholithic complex, Berens River area, northwestern Superior Province, Canada. Geochimica et Cosmochimica Acta, 92, 2979–2995.10.1016/S0016-7037(98)00225-7Search in Google Scholar

Corfu, F., Hanchar, J.M., Hoskin, P.W.O., and Kinny, P. (2003) Atlas of zircon textures. Reviews in Mineralogy and Geochemistry, 53, 469–500.10.1515/9781501509322-019Search in Google Scholar

Crank, J. (1975) The Mathematics of Diffusion, 414 p. Clarendon Press, Oxford.Search in Google Scholar

DeWolf, C.P., Belshaw, N., and O’Nions, R.K. (1993) A metamorphic history from micron-scale 207Pb/206Pb chronometry of Archean monazite. Earth and Planetary Science Letters, 120, 207–220.10.1016/0012-821X(93)90240-ASearch in Google Scholar

Dodson, M.H. (1973) Closure temperature in cooling geochronological and petrological systems. Contributions to Mineralogy and Petrology, 40, 259–274.10.1007/BF00373790Search in Google Scholar

Dohmen, R., Chakraborty, S., Palme, H., and Rammensee, W. (1998) Solid-solid reactions mediated by a gas phase: An experimental study of reaction progress and the role of surfaces in the system olivine+iron metal. American Mineralogist, 83, 970–984.10.2138/am-1998-9-1005Search in Google Scholar

Ellsworth, S., Navrotsky, A., and Ewing, R.C. (1994) Energetics of radiation damage in natural zircon (ZrSiO4). Physics and Chemistry of Minerals, 21, 140–149.10.1007/BF00203144Search in Google Scholar

Faure, G. (1986) Principles of Isotope Geology, 2nd ed., 464 p. Wiley, Chichester.Search in Google Scholar

Federico, L., Capponi, G., Crispini, L., Scambelluri, M., and Villa, I.M. (2005) 39Ar/40Ar dating of high-pressure rocks from the Ligurian Alps: evidence for a continuous subduction-exhumation cycle. Earth and Planetary Science Letters, 240, 668–680.10.1016/j.epsl.2005.09.062Search in Google Scholar

Fisher, C.M., Hanchar, J.M., Miller, C.F., Phillips, S.E., Vervoort, J., and Whitehouse, M.J. (2017) Combining Nd isotopes in monazite and Hf isotopes in zircon to understand complex open-system processes in granitic magmas. Geology, 45, 267–270, 10.1130/G38458.1.Search in Google Scholar

Fitch, F.J., Miller, J.A., and Mitchell, J.G. (1969) A new approach to radio-isotopic dating in orogenic belts. Geological Society of London Special Publications, 3, 157–195.10.1144/GSL.SP.1969.003.01.09Search in Google Scholar

Flude, S., Halton, A.M., Kelley, S.P., Sherlock, S.C., Schwanethal, J., and Wilkinson, C.M. (2014) Observation of centimetre-scale argon diffusion in alkali feldspars: implications for 40Ar/39Ar thermochronology. Geological Society of London Special Publications, 378, 265–275.10.1144/SP378.25Search in Google Scholar

Gebauer, D., Quadt, A.v., Compston, W., Williams, I.S., and Grünenfelder, M. (1988) Archean zircons in a retrograded Caledonian eclogite of the Gotthard massif (Central Alps, Switzerland). Schweizerische Mineralogische und Petrographische Mitteilungen, 68, 485–490.Search in Google Scholar

Giletti, B.J. (1974) Studies in diffusion I: argon in phlogopite mica. In A.W. Hofmann, B.J. Giletti, H.S. Yoder, and R.A. Yund, Eds., Geochemical Transport and Kinetics. Carnegie Institution of Washington Publication, 634, 107–115.Search in Google Scholar

Giletti, B.J., and Tullis, J. (1977) Studies in diffusion, IV. Pressure dependence of Ar diffusion in phlogopite mica. Earth and Planetary Science Letters, 35, 180–183.10.1016/0012-821X(77)90041-3Search in Google Scholar

Glodny, J., Kuhn, A., and Austrheim, H. (2008) Diffusion versus recrystallization processes in Rb-Sr geochronology: isotopic relics in eclogite facies rocks, Western Gneiss region, Norway. Geochimica et Cosmochimica Acta, 72, 506–525.10.1016/j.gca.2007.10.021Search in Google Scholar

Goudie, D.J., Fisher, C.M., Hanchar, J.M., Crowley, J.L., and Ayers, J.C. (2014) Simultaneous in situ determination of U-Pb and Sm-Nd isotopes in monazite by laser ablation ICP-MS. Geochemistry, Geophysics, Geosystems, 15, 2575–2600.10.1002/2014GC005431Search in Google Scholar

Gregory, C.J., McFarlane, C.R.M., Hermann, J., and Rubatto, D. (2009), Tracing the evolution of calc-alkaline magmas: In-situ Sm-Nd isotope studies of accessory minerals in the Bergell Igneous Complex, Italy. Chemical Geology, 260, 73–86.10.1016/j.chemgeo.2008.12.003Search in Google Scholar

Grove, M., and Harrison, T. (1999) Monazite Th–Pb age depth profiling. Geology, 27, 487–490.10.1130/0091-7613(1999)027<0487:MTPADP>2.3.CO;2Search in Google Scholar

Gruber, C., Kutuzov, I., and Ganor, J. (2016) The combined effect of temperature and pH on albite dissolution rate under far-from-equilibrium conditions. Geochimica et Cosmochimica Acta, 186, 154–167.10.1016/j.gca.2016.04.046Search in Google Scholar

Hanchar, J.M., and Miller, C.F. (1993) Zircon zonation patterns as revealed by cathodoluminescence and back-scattered electron images: implications for interpretation of complex crustal histories. Chemical Geology, 110, 1–13.10.1016/0009-2541(93)90244-DSearch in Google Scholar

Hanchar, J.M., and Rudnick, R.L. (1995) Revealing hidden structures: the application of cathodoluminescence and back-scattered electron imaging to dating zircons from lower crustal xenoliths. Lithos, 36, 289–303.10.1016/0024-4937(95)00022-4Search in Google Scholar

Harlov, D.E., and Hetherington, C.J. (2010) Partial high-grade alteration of monazite using alkali-bearing fluids: Experiment and nature. American Mineralogist, 95, 1105–1108.10.2138/am.2010.3525Search in Google Scholar

Harlov, D.E., Wirth, R., and Hetherington, C.J. (2007) The relative stability of monazite and huttonite at 300–900 °C and 200–1000 MPa: Metasomatism and the propagation of metastable mineral phases. American Mineralogist, 92, 1652–1664.10.2138/am.2007.2459Search in Google Scholar

Harlov, D.E., Wirth, R., and Hetherington, C.J. (2011) Fluid-mediated partial alteration in monazite: The role of coupled dissolution-reprecipitation in element redistribution and mass transfer. Contributions to Mineralogy and Petrology, 162, 329–348.10.1007/s00410-010-0599-7Search in Google Scholar

Hart, S.R. (1964) The petrology and isotopic-mineral age relations of a contact zone in the Front Range, Colorado. Journal of Geology, 72, 493–525.10.1086/627011Search in Google Scholar

Hawkins, D.P., and Bowring, S.A. (1997) U-Pb systematics of monazite and xenotime: case studies from the Paleoproterozoic of the Grand Canyon, Arizona. Contributions to Mineralogy and Petrology, 127, 87–103.10.1007/s004100050267Search in Google Scholar

Hetherington, C.J., and Harlov, D.E. (2008) Partial metasomatic alteration of xenotime and monazite from a granitic pegmatite, Hidra anorthosite massif, southwestern Norway: Dissolution-reprecipitation and the subsequent formation of thorite and uraninite inclusions. American Mineralogist, 93, 806–820.10.2138/am.2008.2635Search in Google Scholar

Hetherington, C.J., and Villa, I.M. (2007) Barium silicates of the Berisal Complex, Switzerland: A study in geochronology and rare-gas release systematics. Geochimica et Cosmochimica Acta, 71, 3336–3347.10.1016/j.gca.2007.05.001Search in Google Scholar

Hodges, K.V., Hames, W.E., and Bowring, S.A. (1994) 40Ar/39Ar age gradients in micas from a high-temperature-low-pressure metamorphic terrain; evidence for very slow cooling and implications for the interpretation of age spectra. Geology, 22, 55–58.10.1130/0091-7613(1994)022<0055:AAAGIM>2.3.CO;2Search in Google Scholar

Huyskens, M.H., Zink, S., and Amelin, Y. (2016) Evaluation of temperature-time conditions for the chemical abrasion treatment of single zircons for U–Pb geochronology. Chemical Geology, 428, 25–35.10.1016/j.chemgeo.2016.05.013Search in Google Scholar

Jäger, E. (1967) Die Bedeutung der Biotit Alterswerte. In E. Jäger, E. Niggli, and E. Wenk, Eds., Altersbestimmungen an Glimmern in den Zentralalpen. Beiträge zur Geologischen Karte, Neue Folge, 134, 11–21.Search in Google Scholar

Jamtveit, B. (2010) Metamorphism: from patterns to processes. Elements, 6, 149–152.10.2113/gselements.6.3.149Search in Google Scholar

Jeffery, P.M., and Reynolds, J.H. (1961) Origin of excess Xe129 in stone meteorites. Journal of Geophysical Research, 66, 3582–3583.10.1029/JZ066i010p03582Search in Google Scholar

Kooijman, E., Mezger, K., and Berndt, J. (2010) Constraints on the U–Pb systematics of metamorphic rutile from in situ LA-ICP-MS analysis. Earth and Planetary Science Letters, 293, 321–330.10.1016/j.epsl.2010.02.047Search in Google Scholar

Krogh, T.E. (1970) A simplified technique for the dissolution of zircon and the isolation of uranium and lead. Carnegie Institution of Washington Yearbook, 69, 342–344.Search in Google Scholar

Krogh, T.E. (1971) A low contamination method for decomposition of zircon and the extraction of U and Pb for isotopic age determinations. Carnegie Institution of Washington Yearbook, 70, 258–288.10.1016/0016-7037(73)90213-5Search in Google Scholar

Krogh, T.E. (1973) A low-contamination method for hydrothermal decomposition of zircon and extraction of U and Pb for isotopic age determinations. Geochimica et Cosmochimica Acta, 37, 485–494.10.1016/0016-7037(73)90213-5Search in Google Scholar

Krogh, T.E. (1982a) Improved accuracy of U-Pb zircon dating by selection of more concordant fractions using a high gradient magnetic separation technique. Geochimica et Cosmochimica Acta, 46, 631–635.10.1016/0016-7037(82)90164-8Search in Google Scholar

Krogh, T.E. (1982b) Improved accuracy of U-Pb zircon ages by the creation of more concordant systems using an air abrasion technique. Geochimica et Cosmochimica Acta, 46, 637–649.10.1016/0016-7037(82)90165-XSearch in Google Scholar

Krogh, T.E., and Davis, D. (1975) Alteration in zircons and differential dissolution of altered and metamict zircon. Carnegie Institution of Washington Yearbook, 74, 619–623.Search in Google Scholar

Kula, J., Spell, T.L., and Zanetti, K.A. (2010) 40Ar/39Ar analyses of artificially mixed micas and the treatment of complex age spectra from samples with multiple mica populations. Chemical Geology, 275, 67–77.10.1016/j.chemgeo.2010.04.015Search in Google Scholar

Kusiak, M.A., Whitehouse, M., Wilde, S.A., Nemchin, A.A., and Clark, C. (2013) Mobilization of radiogenic Pb in zircon revealed by ion imaging: Implications for early Earth geochronology. Geology, 41, 291–294.10.1130/G33920.1Search in Google Scholar

Labotka, T.C., Cole, D.R., Fayek, M., Riciputi, L.R., and Stadermann, F.J. (2004) Coupled cation and oxygen-isotope exchange between alkali feldspar and aqueous chloride solution. American Mineralogist, 89, 1822–1825.10.2138/am-2004-11-1229Search in Google Scholar

Laurent, A.T., Seydoux-Guillaume, A.M., Duchêne, S., Bingen, B., Bosse, V., Datas, L. (2016) Sulphate incorporation in monazite lattice and dating the cycle of sulphur in metamorphic belts. Contributions to Mineralogy and Petrology, 171, 94.10.1007/s00410-016-1301-5Search in Google Scholar

Laves, F. (1956) Über die Bedeutung der Barbierit-Analbit-Umwandlung (displacive transformation) für die Erscheinungsformen der Feldspäte in Larvikiten und Rhombenporphyren. Zeitschrift für Kristallographie, 107, 196–201.10.1524/zkri.1956.107.3.196Search in Google Scholar

Mattinson, J.M. (2005) Zircon U–Pb chemical abrasion (“CA–TIMS”) method: combined annealing and multi-step dissolution analysis for improved precision and accuracy of zircon ages. Chemical Geology, 220, 47–66.10.1016/j.chemgeo.2005.03.011Search in Google Scholar

Mattinson, J.M. (2011) Extending the Krogh legacy: development of the CA–TIMS method for zircon U–Pb geochronology. Canadian Journal of Earth Sciences, 48, 95–105.10.1139/E10-023Search in Google Scholar

McFarlane, C.R.M., and McCulloch, M.T. (2007) Coupling of in-situ Sm-Nd systematics and U-Pb dating of monazite and allanite with application to crustal evolution studies. Chemical Geology, 245, 45–60.10.1016/j.chemgeo.2007.07.020Search in Google Scholar

McIntyre, G.A., Brooks, C., Compston, W., and Turek, A. (1966) The statistical assessment of Rb-Sr isochrons. Journal of Geophysical Research, 71, 5459–5468.10.1029/JZ071i022p05459Search in Google Scholar

McLaren, A.C., FitzGerald, J.C., and Williams, I.S. (1994) The microstructure of zircon and its influence on the age determination from Pb/U isotopic ratios measured by ion microprobe. Geochimica et Cosmochimica Acta, 58, 993–1005.10.1016/0016-7037(94)90521-5Search in Google Scholar

Merrihue, C.M. (1965) Trace-element determinations and potassium-argon dating by mass spectroscopy of neutron-irradiated samples. Transactions of the American Geophysical Union, 46, 125.Search in Google Scholar

Merrihue, C.M., and Turner, G. (1966) Potassium-argon dating by activation with fast neutrons. Journal of Geophysical Research, 71, 2852–2857.10.1029/JZ071i011p02852Search in Google Scholar

Mezger, K., and Krogstadt, E.J. (1997) Interpretation of discordant zircon ages: an evaluation. Journal of Metamorphic Geology, 15, 127–140.10.1111/j.1525-1314.1997.00008.xSearch in Google Scholar

Miller, J.S., Matzel, J.E.P., Miller, C.F., Burgess, S.D., and Miller, R.B. (2007) Zircon growth and recycling during the assembly of large, composite arc plutons. Journal of Volcanology and Geothermal Research, 167, 282–299.10.1016/j.jvolgeores.2007.04.019Search in Google Scholar

Mitchell, J.G. (1968) The argon-40/argon-39 method for potassium-argon agedetermination. Geochimica et Cosmochimica Acta, 32, 781–790.10.1016/0016-7037(68)90012-4Search in Google Scholar

Möller, A., O’Brien, P.J., Kennedy, A., and Kröner, A. (2002) Polyphase zircon in ultrahigh-temperature granulites (Rogaland, SW Norway): constraints for Pb diffusion in zircon. Journal of Metamorphic Geology, 20, 727–740.10.1046/j.1525-1314.2002.00400.xSearch in Google Scholar

Müller, W., Kelley, S.P., and Villa I.M. (2002) Dating fault-generated pseudotachylytes: Comparison of 40Ar/39Ar stepwise-heating, laser-ablation and Rb/Sr microsampling analyses. Contributions to Mineralogy and Petrology, 144, 57–77.10.1007/s00410-002-0381-6Search in Google Scholar

Mundil, R., Ludwig, K.R., Metcalfe, I., and Renne, P.R. (2004) Age and timing of the Permian mass extinctions: U/Pb dating of closed-system zircons. Science, 305, 1760–1763.10.1126/science.1101012Search in Google Scholar

Nasdala, L., Hanchar, J.M., Rhede, D., Kennedy, A.K., and Váczi, T. (2010) Complex alteration of zircon: An example from Bancroft, Ontario. Chemical Geology, 269, 290–300.10.1016/j.chemgeo.2009.10.004Search in Google Scholar

Nemchin, A.A., Horstwood, M.S.A., and Whitehouse, M.J. (2013) High-spatialresolution geochronology. Elements, 9, 31–37.10.2113/gselements.9.1.31Search in Google Scholar

Nyfeler, D., Armbruster, T., and Villa, I.M. (1998) Si, Al, Fe order-disorder in Fe-bearing K-feldspar from Madagascar and its implication to Ar diffusion. Schweizerische Mineralogische und Petrographische Mitteilungen, 78, 11–21.Search in Google Scholar

Onstott, T.C., Phillips, D., and Pringle-Goodell, L. (1991) Laser microprobe measurement of chlorine and argon zonation in biotite. Chemical Geology, 90, 145–168.10.1016/0009-2541(91)90040-XSearch in Google Scholar

Paquette, J.L., and Tiepolo, M. (2007) High resolution (5 µm) U–Th–Pb isotope dating of monazite with excimer laser ablation (ELA)-ICP-MS. Chemical Geology, 240, 222–237.10.1016/j.chemgeo.2007.02.014Search in Google Scholar

Parrish, R.R. (1990) U-Pb dating of monazite and its application to geological problems. Canadian Journal of Earth Sciences, 27, 1431–1450.10.1139/e90-152Search in Google Scholar

Paterson, B.E., Stephens, W.E., and Herd, D.A. (1989) Zoning in granitoid accessory minerals as revealed by backscattered electron imagery. Mineralogical Magazine, 53, 55–62.10.1180/minmag.1989.053.369.05Search in Google Scholar

Paterson, B.A., Rogers, G., and Stephens, W.E. (1992a) Evidence for inherited Sm-Nd isotopes in granitoid zircons. Contributions to Mineralogy and Petrology, 111, 378–390.10.1007/BF00311198Search in Google Scholar

Paterson, B.A., Stephens, W.E., Rogers, G., Williams, I.S., Hinton, R.W., and Herd, D.A. (1992b) The nature of zircon inheritance in two granite plutons. Transactions of the Royal Society of Edinburgh, Earth Sciences, 83, 459–471.10.1130/SPE272-p459Search in Google Scholar

Paul, B., Woodhead, J.D., Paton, C., Hergt, J.M., Hellstrom, J., and Norris, C.A. (2012) Multi-phase assemblages: Mineral identification and analysis correction procedures. Geostandards and Geoanalytical Research, 38, 253–263.10.1111/j.1751-908X.2014.00270.xSearch in Google Scholar

Petrus, J.A., Chew, D.M., Leybourne, M.I., and Kamber, B.S. (2017) A new approach to laser-ablation inductively-coupled-plasma mass-spectrometry (LA-ICP-MS) using the flexible map interrogation tool ‘Monocle’. Chemical Geology, 463, 76–93.10.1016/j.chemgeo.2017.04.027Search in Google Scholar

Phillips, D., and Onstott, T.C. (1988) Argon isotopic zoning in mantle phlogopite. Geology, 16, 542–546.10.1130/0091-7613(1988)016<0542:AIZIMP>2.3.CO;2Search in Google Scholar

Piazolo, S., Austrheim, H., and Whitehouse, M.J. (2012) Brittle-ductile microfabrics in naturally deformed zircon: Deformation mechanisms and consequences for U-Pb dating. American Mineralogist, 97, 1544–1563.10.2138/am.2012.3966Search in Google Scholar

Piazolo, S., La Fontaine, A., Trimby, P., Harley, S., Yang, L., Armstrong, R., and Cairney, J.M. (2016) Deformation-induced trace element redistribution in zircon revealed using atom probe tomography. Nature Communications, 7, 10490.10.1038/ncomms10490Search in Google Scholar

Plümper, O., and Putnis, A. (2009) The complex hydrothermal history of granitic rocks: Multiple feldspar replacement reactions under subsolidus conditions. Journal of Petrology, 50, 967–987.10.1093/petrology/egp028Search in Google Scholar

Putnis, A. (2002) Mineral replacement reactions: from macroscopic observations to microscopic mechanisms. Mineralogical Magazine, 66, 689–708.10.1180/0026461026650056Search in Google Scholar

Putnis, A. (2009) Mineral replacement reactions. Reviews in Mineralogy and Geochemistry, 70, 87–124.10.1515/9781501508462-005Search in Google Scholar

Putnis, A., and Austrheim, H. (2013) Mechanisms of metasomatism and metamorphism on the local mineral scale: The role of dissolution-reprecipitation during mineral re-equilibration. In D.E. Harlov and H. Austrheim, Eds., Metasomatism and the Chemical Transformation of Rock, p. 141–170. Springer, Heidelberg.10.1007/978-3-642-28394-9_5Search in Google Scholar

Reynolds, J.H. (1963) Xenology. Journal of Geophysical Research, 68, 2939–2956.10.1029/JZ068i010p02939Search in Google Scholar

Rittner, M., and Müller, W. (2012) 2D mapping of LA-ICP-MS trace element distributions using R. Computers and Geosciences, 42, 152–161.10.1016/j.cageo.2011.07.016Search in Google Scholar

Romer, R.L. (1996) U-Pb systematies of stilbite-bearing low-temperature mineral assemblages from the Malmberget iron ore, northern Sweden. Geochimica et Cosmochimica Acta, 60, 1951–1961.10.1016/0016-7037(96)00066-XSearch in Google Scholar

Schoene, B., Latkoczy, C., Schaltegger, U., and Günter, D. (2010) A new method integrating high-precision U-Pb geochronology with zircon trace element analysis (U-Pb TIMS-TEA). Geochimica et Cosmochimica Acta, 74, 7144–7159.10.1016/j.gca.2010.09.016Search in Google Scholar

Silver, L.T., and Deutsch, S. (1963) Uranium-lead isotopic variations in zircon: a case study. Journal of Geology, 71, 721–758.10.1086/626951Search in Google Scholar

Steiger, R.H., Bickel, R.A., and Meier, M. (1993) Conventional U-Pb dating of single fragments of zircon for petrogenetic studies of Phanerozoic granitoids. Earth and Planetary Science Letters, 115, 197–209.10.1016/0012-821X(93)90222-USearch in Google Scholar

Stern, R.A., and Berman, R.G. (2001) Monazite U–Pb and Th–Pb geochronology by ion microprobe, with an application to in situ dating of an Archean metasedimentary rock. Chemical Geology, 172, 113–130.10.1016/S0009-2541(00)00239-4Search in Google Scholar

Tartèse, R., Ruffet, G., Poujol, M., Boulvais, P., and Ireland, T.R. (2011) Simultaneous resetting of the muscovite K-Ar and monazite U-Pb geochronometers: a story of fluids. Terra Nova, 23, 390–398.10.1111/j.1365-3121.2011.01024.xSearch in Google Scholar

Tera, F., and Wasserburg, G.J. (1972a) U-Th-Pb systematics in three Apollo 14 basalts and the problem of initial Pb in lunar rocks. Earth and Planetary Science Letters, 14, 281–304.10.1016/0012-821X(72)90128-8Search in Google Scholar

Tera, F., and Wasserburg, G.J. (1972b) U–Th–Pb systematics in lunar highland samples from the Luna 20 and Apollo 16 missions. Earth and Planetary Science Letters, 17, 36–51.10.1016/0012-821X(72)90257-9Search in Google Scholar

Tilton, G.R. (1960) Volume diffusion as a mechanism for discordant lead ages. Journal of Geophysical Research, 65, 2933–2945.10.1029/JZ065i009p02933Search in Google Scholar

Turner, G. (1965) Extinct iodine 129 and trace elements in chondrites. Journal of Geophysical Research, 70, 5433–5445.10.1029/JZ070i021p05433Search in Google Scholar

Turner, G., Huneke, J.C., Podosek, F.A., and Wasserburg, G.J. (1971) 40Ar-39Ar ages and cosmic ray exposure age of Apollo 14 samples. Earth and Planetary Science Letters, 12, 19–35.10.1016/0012-821X(71)90051-3Search in Google Scholar

Ubide, T., McKenna, C.A., Chew, D.M., and Kamber, B.S. (2015) High-resolution LA-ICP-MS trace element mapping of igneous minerals. Chemical Geology, 409, 157–168.10.1016/j.chemgeo.2015.05.020Search in Google Scholar

Valley, J.W., Cavosie, A.J., Ushikubo, T., Reinhard, D.A., Lawrence, D.F., Larson, D.J., Clifton, P.H., Kelly, T.F., Wilde, S.A., Moser, D.E., and Spicuzza, M.J. (2014) Hadean age for a post-magma-ocean zircon confirmed by atom-probe tomography. Nature Geoscience, 7, 219–223.10.1038/ngeo2075Search in Google Scholar

Vavra, G. (1990) On the kinematics of zircon growth and its petrogenetic significance: a cathodoluminescence study. Contributions to Mineralogy and Petrology, 106, 90–99.10.1007/BF00306410Search in Google Scholar

Vavra, G., and Hansen, B.T. (1991) Cathodoluminescence studies and U/Pb dating of zircons in pre-Mesozoic gneisses of the Tauern Window: Implications for the Penninic basement evolution. Geologische Rundschau, 80, 703–715.10.1007/BF01803696Search in Google Scholar

Villa, I.M. (2001) Radiogenic isotopes in fluid inclusions. Lithos, 55, 115–124.10.1016/S0024-4937(00)00041-4Search in Google Scholar

Villa, I.M. (2006) From the nm to the Mm: isotopes, atomic-scale processes, and continent-scale tectonic models. Lithos, 87, 155–173.10.1016/j.lithos.2005.06.012Search in Google Scholar

Villa, I.M. (2010) Disequilibrium textures vs equilibrium modelling: Geochronology at the crossroads. In M.I. Spalla, A.M. Marotta, and G. Gosso, Eds., Advances in Interpretation of Geological Processes. Geological Society of London Special Publications, 332, 1–15.10.1144/SP332.1Search in Google Scholar

Villa, I.M. (2016) Diffusion in mineral geochronometers: present and absent. Chemical Geology, 420, 1–10.10.1016/j.chemgeo.2015.11.001Search in Google Scholar

Villa, I.M., and Puxeddu, M. (1994) Geochronology of the Larderello geothermal field: new data and the “closure temperature” issue. Contributions to Mineralogy and Petrology, 115, 415–426.10.1007/BF00320975Search in Google Scholar

Villa, I.M., and Williams, M.L. (2013) Geochronology of metasomatic events. In D.E. Harlov and H. Austrheim, Eds., Metasomatism and the Chemical Transformation of Rock, p. 171–202. Springer, Heidelberg.10.1007/978-3-642-28394-9_6Search in Google Scholar

Villa, I.M., Grobéty, B., Kelley, S.P., Trigila, R., and Wieler, R. (1996) Assessing Ar transport paths and mechanisms for McClure Mountains hornblende. Contributions to Mineralogy and Petrology, 126, 67–80.10.1007/s004100050236Search in Google Scholar

Villa, I.M., Hermann, J., Müntener, O., and Trommsdorff, V. (2000) 39Ar-40Ar dating of multiply zoned amphibole generations (Malenco, Italian Alps). Contributions to Mineralogy and Petrology, 140, 363–381.10.1007/s004100000197Search in Google Scholar

Villa, I.M., Bucher, S., Bousquet, R., Kleinhanns, I.C., and Schmid, S.M. (2014) Dating polygenetic metamorphic assemblages along a transect through the Western Alps. Journal of Petrology, 55, 803–830.10.1093/petrology/egu007Search in Google Scholar

Wartho, J.A., Kelley, S.P., Brooker, R.A., Carroll, M.R., Villa, I.M., and Lee, M.R. (1999) Direct Ar diffusion measurements in a gem-quality Madagascar K-feldspar using the Ultra-Violet Laser Ablation Microprobe (UVLAMP). Earth and Planetary Science Letters, 170, 141–153.10.1016/S0012-821X(99)00088-6Search in Google Scholar

Wetherill, G.W. (1956) Discordant uranium-lead ages 1. Transactions, American Geophysical Union, 37, 320–326.10.1029/TR037i003p00320Search in Google Scholar

Wetherill, G.W. (1963) Discordant uranium-lead ages 2. Discordant ages resulting from diffusion of lead and uranium. Journal of Geophysical Research, 68, 2957–2965.10.1029/JZ068i010p02957Search in Google Scholar

Whitehouse, M.J., Kumar, G.R.R., and Rimša, A. (2014) Behaviour of radiogenic Pb in zircon during ultrahigh-temperature metamorphism: an ion imaging and ion tomography case study from the Kerala Khondalite Belt, southern India. Contributions to Mineralogy and Petrology, 168, 1–18.10.1007/s00410-014-1042-2Search in Google Scholar

Wijbrans, J.R., and McDougall, I. (1986) Ar-40/Ar-39 dating of white micas from an Alpine high-pressure metamorphic belt on Naxos (Greece)—the resetting of the argon isotopic system. Contributions to Mineralogy and Petrology, 93, 187–194.10.1007/BF00371320Search in Google Scholar

Williams, M.L., Jercinovic, M.J., and Hetherington, C.J. (2007) Microprobe monazite geochronology: Understanding geologic processes by integrating composition and chronology. Annual Reviews in Earth and Planetary Science, 35, 137–175.10.1146/annurev.earth.35.031306.140228Search in Google Scholar

Williams, M.L., Jercinovic, M.J., Harlov, D.E., Budzyń, B., and Hetherington, C.J. (2011) Resetting monazite ages during fluid-related alteration. Chemical Geology, 283, 218–225.10.1016/j.chemgeo.2011.01.019Search in Google Scholar

Wood, B.J., and Walther, J.V. (1983) Rates of hydrothermal reactions. Science, 222, 413–415.10.1126/science.222.4622.413Search in Google Scholar PubMed

Zhou, L., McKenna, C.A., Long, D.G.F., and Kamber, B.S. (2017) LA-ICP-MS elemental mapping of pyrite: An application to the Palaeoproterozoic atmosphere. Precambrian Research, 297, 22–55.10.1016/j.precamres.2017.05.008Search in Google Scholar

Received: 2017-1-22
Accepted: 2017-7-3
Published Online: 2017-11-30
Published in Print: 2017-12-20

© 2017 Walter de Gruyter GmbH, Berlin/Boston

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