Dear William,
You may consulate a paper in J. Geol. (1998) 106:97-104 in which there
is a discussion
of causes for unusually positive d13C values in marls (the third
paragraph on page 100).
Yong-Fei


William P. Patterson wrote:
>
> I've been asked to approach the listserve with several questions.
>
> Two research projects currently underway here at Syracuse University have
> uncovered some rather extreme and as of yet somewhat unexplained d13C values.
>
> Holocene marl d13C values from Bolivia varies from a high of about +16 per
> mil PDB
> down to what could be considered more conventional lacustrine values (+2 to
> +4 per mil PDB).
>
> A Holocene marl core from the Finger Lakes region on central New York State
> (Cayuga Lake) has yielded bulk aquatic organic matter with a d13C value of
> -33 per mil PDB and a
> radiocarbon date which is about 2 thousand years too young (in reference
> to14C dates on bracketing organic matter). These organic matter d13C values
> are therefore about 6 per mil lower than would be expected.
>
> Our question is.....has anyone obtained similar data or know of any
> published explanation for such values?
>
> Thanks, I'll pass any info along!
> Bill
>
> William P. Patterson
> Syracuse University
> Department of Earth Sciences
> Syracuse, NY 13244-1070
> Phone: 315-443-3869
> FAX: 315-443-3363
> http://128.230.24.91/Bill.html
> Mórán cainte ar bheagán cúise

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Dr. Yong-Fei Zheng
Department of Earth and Space Sciences
University of Science and Technology of China
Hefei 230026, PR China
Tel.: (+86) 551 3603384        Fax: (+86) 551 3603554
Email: [log in to unmask]
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