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Table 1 U–Pb isotopic data for ID-TIMS zircon analyses

From: Integrated Ladinian bio-chronostratigraphy and geochrononology of Monte San Giorgio (Southern Alps, Switzerland)

Samplea Concentrations Isotopic ratios Isotopic ages
Th/Ub 206Pb* mol% Pb*/Pbcc Pbc 206Pb/204Pbd 208Pb/206Pbe 207Pb/206Pbe % errf 207Pb/235Ue % errf 206Pb/238Ue % errf corr. 207Pb/206Pbg ±f 207Pb/235Ug ±f 206Pb/238Ug ±f
×10−13molc 206Pb*c (pg)c coef.
RS09/5a                     
 z1 0.306 0.9122 99.34 43 0.50 2748 0.097 0.050988 0.164 0.266895 0.243 0.037964 0.109 0.833 239.35 3.77 240.21 0.52 240.30 0.26
 z2 0.447 2.4444 99.73 110 0.55 6771 0.142 0.050919 0.127 0.265565 0.200 0.037826 0.097 0.861 236.29 2.92 239.14 0.43 239.43 0.23
 z4 0.392 5.2720 99.85 191 0.67 11882 0.124 0.051266 0.100 0.281635 0.178 0.039843 0.089 0.937 251.95 2.30 251.95 0.40 251.95 0.22
 z3 0.471 1.4778 98.29 17 2.13 1066 0.150 0.051268 0.324 0.267922 0.386 0.037902 0.093 0.731 252.02 7.45 241.03 0.83 239.90 0.22
 z2b 0.441 0.2935 97.93 14 0.51 880 0.140 0.051019 0.453 0.268756 0.555 0.038205 0.231 0.606 240.83 10.45 241.70 1.19 241.79 0.55
 z14 0.379 1.4676 99.31 42 0.84 2650 0.120 0.051052 0.179 0.267566 0.245 0.038011 0.094 0.800 242.30 4.12 240.75 0.53 240.59 0.22
 z13 0.440 0.2935 97.93 14 0.51 880 0.140 0.051019 0.453 0.267590 0.527 0.038040 0.154 0.591 240.82 10.45 240.77 1.13 240.76 0.36
 z12 0.726 0.5516 98.07 16 0.90 943 0.231 0.051116 0.379 0.266608 0.444 0.037828 0.115 0.658 245.28 8.73 239.98 0.95 239.44 0.27
 z10 0.321 0.7184 96.08 7 2.43 464 0.102 0.050910 0.707 0.265832 0.784 0.037871 0.127 0.661 235.82 16.31 239.36 1.67 239.72 0.30
 z9 0.379 0.4549 98.48 19 0.58 1198 0.121 0.051528 0.611 0.276086 0.679 0.038860 0.106 0.684 263.64 14.03 247.55 1.49 245.85 0.26
                Weighted mean age 239.51 ± 0.15 MSWD = 1.3
Ca31                     
 z1 0.520 0.5576 97.27 11 1.29 677 0.164 0.050846 0.598 0.266712 0.680 0.038044 0.215 0.513 232.98 13.81 240.06 1.45 240.78 0.51
 z2 0.475 0.4100 99.19 37 0.28 2281 0.151 0.051025 0.223 0.267456 0.288 0.038016 0.106 0.724 241.08 5.15 240.66 0.62 240.61 0.25
 z3 0.695 1.3885 99.57 74 0.49 4290 0.221 0.051019 0.124 0.267397 0.227 0.038012 0.138 0.881 240.92 2.85 240.61 0.49 240.58 0.33
 z4 0.581 1.1072 99.38 50 0.57 2979 0.184 0.051090 0.199 0.268223 0.275 0.038077 0.129 0.740 244.07 4.59 241.27 0.59 240.98 0.31
 z5 0.500 0.6214 98.98 30 0.52 1819 0.159 0.051025 0.258 0.267240 0.318 0.037986 0.103 0.685 241.09 5.95 240.48 0.68 240.42 0.24
                Weighted mean age 240.63 ± 0.13 MSWD = 2.2
RS09/4                     
 z1 0.701 0.3528 98.34 19 0.49 1099 0.223 0.051279 0.350 0.271502 0.421 0.038400 0.136 0.642 252.64 8.04 243.89 0.91 242.99 0.32
 z2 0.816 0.7247 99.12 37 0.53 2071 0.259 0.051059 0.239 0.268786 0.308 0.038180 0.122 0.701 242.73 5.50 241.72 0.66 241.62 0.29
 z4 0.737 0.3105 96.47 9 0.94 516 0.235 0.051420 0.648 0.271770 0.722 0.038332 0.117 0.685 258.96 14.89 244.11 1.57 242.57 0.28
 z5 0.612 1.1649 98.87 27 1.11 1605 0.194 0.051081 0.232 0.268197 0.296 0.038079 0.092 0.778 243.69 5.34 241.25 0.64 241.00 0.22
 z6 0.644 0.6983 96.41 8 2.15 507 0.205 0.051111 0.640 0.268737 0.713 0.038134 0.111 0.696 245.03 14.75 241.68 1.53 241.34 0.26
 z7 0.612 0.7050 98.85 27 0.68 1587 0.194 0.050978 0.242 0.267589 0.306 0.038070 0.094 0.764 239.03 5.58 240.76 0.66 240.94 0.22
 z8 0.758 0.3251 92.89 4 2.06 256 0.242 0.051630 1.295 0.277326 1.407 0.038957 0.178 0.671 268.30 26.69 248.53 3.10 246.45 0.43
                Weighted mean age 241.07 ± 0.13 MSWD = 3.0
  1. az1, z2 etc. are labels for fractions composed of single zircon grains or fragments; all fractions annealed and chemically abraded after Mattinson (2005)
  2. bModel Th/U ratio calculated from radiogenic 208Pb/206Pb ratio and 207Pb/235U age
  3. c Pb* and Pbc represent radiogenic and common Pb, respectively; mol % 206Pb* with respect to radiogenic, blank and initial common Pb
  4. dMeasured ratio corrected for spike and fractionation only
  5. eCorrected for fractionation, spike, and common Pb; up to 1 pg of common Pb was assumed to be procedural blank: 206Pb/204Pb = 18.50 ± 0.50 %; 207Pb/204Pb = 15.8 ± 0.5 %; 208Pb/204Pb = 38.02 ± 0.75 % (all uncertainties 1σ). Excess over blank was assigned to initial common Pb
  6. fErrors are 2σ, propagated using the algorithms of Schmitz and Schoene (2007) and Crowley et al. (2007)
  7. gCalculations are based on the decay constants of Jaffey et al. (1971). 206Pb/238U and 207Pb/206Pb ages corrected for initial disequilibrium in 230Th/238U using Th/U (magma) = 4
  8. 206Pb/238U values (including errors) of zircons forming populations of coherent and equivalent analyses are indicated in bold