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Table 3 Comparison of strontium-model ages with available bio- and sequence-stratigraphical ages, for each lithostratigraphical formation and member studied here. The uncertainty attributed to each 87Sr/86Sr age are derived from the 2σmean given in Table 1, and are calculated both for maximal and minimal values for each lithostratigraphic interval. Minimal, maximal, range and mean 87Sr/86Sr values are also reported for each formation and member

From: Reconciling strontium-isotope and K–Ar ages with biostratigraphy: the case of the Urgonian platform, Early Cretaceous of the Jura Mountains, Western Switzerland

Formation

87Sr/86Sr from well-preserved rhynchonellids

87Sr/86Srbelemnites age (Ma)

Bio- or sequence-stratigraphic age (Ma)

Number

Minimum

Maximum

Range

Mean

Maximal

Minimal

Chronostrat.

Mean

Age range

Chronostrat.

Source

Marnes bleues d’Hauterive

5

0.707413

0.707434

0.000021

0.707423

133.35 ± 0.02

133.23 ± 0.02

E. Hauterivian

133.29

~133.2–133.9

M.E.Hauterivian

Ammonites

Marnes d’Uttins

3

0.707448

0.707507

0.000059

0.707473

132.22 ± 0.02

131.14 ± 0.04

I.E. Haut.-L.Haut.

131.68

~132.7–131.6

L.E.-E.L. Haut.

Ammonites

Urgonien Jaune

2

0.707437

0.707477

0.000040

0.707457

129.80 ± 0.16

126.08 ± 0.26

E.-L. Barremian

127.94

~127.5–126.8

M.L. Barremian

Nannofossils

Marnes de la Russille

3

0.707443

0.707513

0.000070

0.707474

129.34 ± 0.17

126.16 ± 0.18

m.E.-m.L. Barr.

127.75

~127.6–127.4

M.L. Barremian

Seq. stratigr.

Urgonien Blanc

1

0.707490

0.707490

 

0.707490

128.36 ± 0.22

128.36 ± 0.22

I.E.-e.L. Barr.

128.36

~127.4–126.7

L.L.Barremian

Seq. stratigr