Continental weathering as the source of iron in Jurassic iron oolites from Switzerland

Swiss Journal of Geosciences

Table 4 Neodymium and iron isotope compositions for the reductive leachates of iron oolites

Sample	Age (Ma)	¹⁴³Nd/¹⁴⁴Nd (measured)	2 SEM	¹⁴⁷Sm/¹⁴⁴Nd	εNd (initial)	2 SEM	δ⁵⁶Fe (‰) (measured)	2 SEM (‰)	δ⁵⁶Fe (‰) (authigenic)
H1	163	0.512222	0.000005	0.1625	− 7.41	0.11	− 1.44	0.03	− 1.49
H2	172	0.512114	0.000005	0.1156	− 8.44	0.09	− 0.94	0.05	− 0.95
WG1	167	0.512139	0.000005	0.1651	− 9.07	0.10	− 0.83	0.04	− 0.83
WG3	167	0.512134	0.000004	0.1343	− 8.50	0.08	− 0.82	0.03	− 0.82
EE-P4	165	0.512226	0.000004	0.1860	− 7.81	0.08	–	–	–
EE-P6	165	0.512179	0.000004	0.1416	− 7.80	0.08	–	–	–
EE-P7	165	0.512181	0.000005	0.1567	− 8.08	0.09	–	–	–
EE-P9	165	0.512186	0.000005	0.1474	− 7.79	0.09	− 0.71	0.04	− 0.72
EE-P12	165	0.512164	0.000004	0.1220	− 7.68	0.08	–	-	–
EE-P18	165	0.512183	0.000004	0.1481	− 7.86	0.08	− 0.65	0.04	− 0.66
EE-P20	165	0.512182	0.000004	0.1350	− 7.59	0.08	–	–	–
EE-P22	165	0.512173	0.000005	0.1511	− 8.11	0.09	–	–	–
EE-P23	165	0.512153	0.000005	0.2267	− 10.10	0.10	–	–	–
EE-P26	165	0.512197	0.000005	0.1311	− 7.23	0.10	–	–	–
EE-P28	165	0.512151	0.000004	0.1131	− 7.75	0.08	− 0.56	0.02	− 0.57
EE-P30	165	0.512147	0.000004	0.1438	− 8.47	0.08	–	–	–
EE-P31	165	0.512142	0.000005	0.1264	− 8.20	0.09	–	–	–
EE-P32	165	0.512117	0.000004	0.1327	− 8.81	0.08	–	–	–
EE-P33	165	0.512109	0.000004	0.1353	− 9.03	0.08	–	–	–

External errors on εNd correspond to 0.15 epsilon-units and to < 1‰ for ¹⁴⁷Sm/¹⁴⁴Nd (Sect. 3). Measured Fe isotope compositions are, for most samples, averages of two analyses, with an external uncertainty of \(\pm\) 0.08‰ (2 SD, Sect. 3). Authigenic Fe isotope compositions reflect measured compositions corrected for detrital contributions (Sect. 4)