Geochemical investigation of the mixed Máriahalom vertebrate fauna at the Paleogene–Neogene boundary in the Central Paratethys: environmental conditions and age constrain

Swiss Journal of Palaeontology

Table 2 Strontium isotope ratios, related ages, and in case of the calcareous fossils X-ray diffraction, stable isotope composition, and minor and trace element ratio data. Abbreviations: arg - aragonite, cal - calcite, q - quartz.

Sample		⁸⁷Sr/⁸⁶Sr	*2SE 10**^–6	SIS Age			Mineralogy (%)			δ¹³C ‰, VPDB	1SD	δ¹⁸O ‰, VPDB	1SD	Yield % (CaCO₃)	Mg/Ca	Sr/Ca	Fe/Ca	Mn/Ca
Sample		⁸⁷Sr/⁸⁶Sr	*2SE 10**^–6	−	My	+	q	cal	arg	δ¹³C ‰, VPDB	1SD	δ¹⁸O ‰, VPDB	1SD	Yield % (CaCO₃)	mmol/mol
Aragonite
Glycymeris—bivalve	G1	0.708358	5	0.3	21.3	0.3	–	8	92	1.24	0.06	−1.97	0.08	96	8.31	1.40	0.49	0.04
Nerineidae-gastropoda	N1	0.708355	5	0.3	21.4	0.4	–	1	99	−0.61	0.04	−2.83	0.09	102	5.78	1.34	1.16	0.07
Calcite
Ostrea—bivalve	O2	0.708189	5	0.4	24.2	0.4	0.5	98.5	1	−2.86	0.06	−4.89	0.07	101	11.15	0.63	0.82	0.20
Apatite
Shark tooth enameloid	SE1	0.708338	4	0.3	21.6	0.4
Shark tooth enameloid	SE3	0.708406	4	0.3	20.6	0.3
Shark tooth root	SR2	0.708898	3	0.9	9.6	0.8

It is noted that the calcareous fossils largely preserved their original mineralogy. The Sr isotope ages are derived from McArthur et al. (2020), and the upper and lower age limits were calculated based on the 95% confidence limit of the curve and the error related to the Sr isotope analyses. As the internal reproducibility of the individual analyses is lower than that of the external one derived from repeated analyses of the NIST SRM 987 standard (18 ppm, 2SD, n = 14); hence, this later was used to calculate error on the ages.
It is noted that the suggested age for the Máriahalom site derives from the specimens G1, N1, and SE1 (21.4 ± 0.5 Ma). The name of these specimens and their SIS ages are marked bold.