Strontium Isotope Stratigraphy

We use strontium isotope stratigraphy to solve geological problems, primarily to date sediments undatable by other means. Publications that have resulted from this work are listed below . The group collaborates widely with groups across the globe. Proposals for collaborative work are welcome. Consultancy work is sometimes undertaken.

The University of London Strontium Isotope Stratigraphy Group has contributed to the construction of the global seawater strontium curve (McArthur et al. 1993, 1994, 1998; 2000b, 2007; Mc Laughlin et al. 1995) and provided a user-friendly table (as a spreadsheet) for the rapid and easy conversion of 87Sr/86Sr values to numerical age (Howarth and McArthur 1997; Howarth and McArthur 2001; McArthur and Howarth 2004; CLICK HERE TO SEE THE TABLE,

We have used strontium isotope stratigraphy to date Pliocene, Miocene, and Maastrichtian strata in Antarctica that otherwise were undatable (Dingle et al., 1997; Crame et al. 1999, McArthur et al. 2000a); resolve age conflicts in Argentina (Scasso et al. 2001) and date phosphogenic events (McArthur et al. 1990). We have also published reviews on strontium isotope stratigraphy that are of use to undergraduates (McArthur, 1991, 1992, 1997) and researchers (McArthur 1994, McArthur and Howarth 2004). Currently, a particular interest is to see just how good strontium isotope stratigraphy can be; multiple replicate analysis of good material can, in our laboratory, give uncertainties, calculated as ± 2 s.e., on mean values of 87Sr/86Sr that are as good as ± 0.000 003 (i.e. ± 3 x 10-6). Such precision in analysis yields a resolution in correlation that, for example, in Late Cretaceous and Jurassic strata (McArthur et al. 2000a,b) is as good as that potentially available with ammonites.

For more information, contact John M. McArthur

Selected Publications on Sr Isotope Stratigraphy:

J.M. McArthur (2008). Comment on “Comment on “The impact of the Central Atlantic Magmatic Province on climate and on the Sr- and Os-isotope evolution of seawater” by Cohen A.S. and Coe A.L. 2007, Palaeogeography, Palaeoclimatology, Palaeoecology, 244, 374–390. Palaeogeography, Palaeoclimatology, Palaeoecology, 258, 334–338.

S.N. Ehrenberg, N.A.H. Pickard, G. Laursen, S. Monibi, Z.K. Mossadegh, T.A. Svånå, A.A.M. Aqrawi, J.M. McArthur and M.F. Thirlwall (2007). Strontium isotope stratigraphy of the Asmari Formation (Oligocene-Miocene), southwest Iran.  Journal of Petroleum Geology, 30, 107–128.

J.M. McArthur and Wignall P. (2007). Comment on “Non-uniqueness and interpretation of the seawater 87Sr/86Sr curve”  by Dave Waltham and Darren R. Gröcke (GCA, 70, 2006, 384–394). Geochim. Cosmochim. Acta (2007), doi: 10.1016/j.gca.2006.10.026.

J.M. McArthur, N.M.M. Janssen, S. Reboulet, M.J. Leng, M.F. Thirlwall  and B. van de Schootbrugge (2007). Early Cretaceous ice-cap volume, palaeo-temperatures (Mg, δ18O), and  isotope stratigraphy (δ13C, 87Sr/86Sr) from Tethyan belemnites. Palaeogeography, Palaeoclimatology, Palaeoecology, 248, 391–430.

J.M. McArthur, D. Rio, F. Massari, D. Castradori, T.R. Bailey, M. Thirlwall. and S. Houghton (2006). A revised Pliocene record for marine-87Sr/86Sr used to date an interglacial event, Cockburn Island Formation, northern Antarctic Peninsula. Palaeogeography, Palaeoclimatology, Palaeoecology, 242, 126–136.

J.L. Smellie, J.M. McArthur, W.C. McIntosh and R. Esser (2006). Late Neogene interglacial events in the James Ross Island region, northern Antarctic Peninsula, dated by Ar/Ar and Sr-isotope stratigraphy. Palaeogeography, Palaeoclimatology, Palaeoecology,  242, 169–187.

S.N. Ehrenberg, J.M. McArthur and M.F. Thirlwall (2006). Growth, demise, and dolomitization of Miocene carbonate platforms, Marion Plateau, offshore NE Australia. Jour. Sedimentary Research. 76, 91–116. DOI: 10.2110/jsr.2006.06.