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

Stockar, Rudolf; Baumgartner, Peter O.; Condon, Daniel

doi:10.1007/s00015-012-0093-5

Swiss Journal of Geosciences

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)

Sample^a	Concentrations					Isotopic ratios									Isotopic ages
	Th/U^b	²⁰⁶Pb*	mol%	Pb*/Pbc^c	Pbc	²⁰⁶Pb/²⁰⁴Pb^d	²⁰⁸Pb/²⁰⁶Pb^e	²⁰⁷Pb/²⁰⁶Pb^e	% err^f	²⁰⁷Pb/²³⁵U^e	% err^f	²⁰⁶Pb/²³⁸U^e	% err^f	corr.	²⁰⁷Pb/²⁰⁶Pb^g	±^f	²⁰⁷Pb/²³⁵U^g	±^f	²⁰⁶Pb/²³⁸U^g	±^f
	Th/U^b	×10⁻¹³mol^c	²⁰⁶Pb*^c	Pb*/Pbc^c	(pg)^c	²⁰⁶Pb/²⁰⁴Pb^d	²⁰⁸Pb/²⁰⁶Pb^e	²⁰⁷Pb/²⁰⁶Pb^e	% err^f	²⁰⁷Pb/²³⁵U^e	% err^f	²⁰⁶Pb/²³⁸U^e	% err^f	coef.	²⁰⁷Pb/²⁰⁶Pb^g	±^f	²⁰⁷Pb/²³⁵U^g	±^f	²⁰⁶Pb/²³⁸U^g	±^f
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

^az1, z2 etc. are labels for fractions composed of single zircon grains or fragments; all fractions annealed and chemically abraded after Mattinson (2005)
^bModel Th/U ratio calculated from radiogenic ²⁰⁸Pb/²⁰⁶Pb ratio and ²⁰⁷Pb/²³⁵U age
^c Pb* and Pbc represent radiogenic and common Pb, respectively; mol % ²⁰⁶Pb* with respect to radiogenic, blank and initial common Pb
^dMeasured ratio corrected for spike and fractionation only
^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
^fErrors are 2σ, propagated using the algorithms of Schmitz and Schoene (2007) and Crowley et al. (2007)
^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
206Pb/238U values (including errors) of zircons forming populations of coherent and equivalent analyses are indicated in bold

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