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>Myself and Dr. Graham Leslie are interested in the chronology of Dalradian
>events in Scotland and Ireland: me on sequence strat., he on structural
>geology. We have some sulphur isotope data from mineralisation events and
>are asking for any information on the most recent work/revision of the
>sulphur isotope curve for the Cambrian, Ordovician, and if by any chance
>anyone has it, the late Precambrian?
>
>I'd be glad of any help.
>
>Thanks
>
Hi Alistair,

The late Precambrian curve is poorly constrained but I have the earliest
Cambrian data for chinese phosphates, with reliable 'seawater' d34S values
all higher than +30 for the earliest stage of the Cambrian as was implied
by data in the well known Claypool et al. paper from 1980. There are more
data around for pyrites including Ross et al. in Precambrian Research 73,
71-99 (1995), and much work for the Precambrian is summed up in Canfield
and Teske in Nature 382, 127-132. There are also abundant pyrite/barite
data for Dalradian barite mineralisation in Scotland, and Dalradian age
equivalent deposits in China and Brazil, which I can dig out for you if you
like. If you would like more information, please email me directly in
Strasbourg, yours

Graham


Graham Shields
Centre de Géochimie de la Surface
CNRS, 1 rue Blessig, F-67084
Strasbourg Cedex, France
Tel: 00 33 3 88 35 85 28
Fax: 00 33 3 88 36 72 35