Skip to main content

Table 1 Measured rutile and titanite U–Pb ages for the three studied samples from the Ur Breccia

From: Paleocene metamorphism along the Pennine–Austroalpine suture constrained by U–Pb dating of titanite and rutile (Malenco, Alps)

SampleIsochron ageIsochron typeCommon Pb composition
Age (Ma)± (95% conf.)MSWDnaConcordia typeAnchored isochron?207Pb/206PbcommonSourceIsochron slopeb
Titanite ages
19–8538160.37/7WetherillUn-anchored0.809 ± 0.037Isochron slope0.00897 ± 0.00039
28–205751.220/20WetherillUn-anchored0.841 ± 0.023Isochron slope0.00863 ± 0.00023
60–6548111.810/10WetherillUn-anchored0.819 ± 0.026Isochron slope0.00886 ± 0.00027
Pooled (3 samples)54.73.91.337/37WetherillUn-anchored0.833 ± 0.014Isochron slope0.008706 ± 0.00014
Rutile ages
19–8563.02.71.319/20 [26]Tera-WasserburgAnchored0.839 ± 0.015cStacey–Kramers 60 Ma 
28–206172.611/11 [23]Tera-WasserburgAnchored0.839 ± 0.015cStacey–Kramers 60 Ma 
Pooled (2 samples)62.43.31.930/31 [49]Tera-WasserburgAnchored0.839 ± 0.015cStacey–Kramers 60 Ma 
  1. an indicates the number of analyses included in the calculation of the age, as a fraction of the total number of analyses. For rutile, only analyses for which 207Pb was distinguishable from background (> 50 cps) are included in this total; the total number of analyses including those with < 50 cps 207Pb is given in square brackets
  2. bThe measured slope of isochrons is given for un-anchored Wetherill concordia only; for these isochrons the 207Pb/206Pbcommon was calculated from the isochron slope as described in text
  3. cFor anchored Tera-Wasserburg isochrons, the quoted 207Pb/206Pbcommon is an assumed model common Pb composition (Stacey and Kramers 1975), and is not inferred from the isochron itself