Hello,
   I am an isotope and marine organic geochemist (MIT/Woods Hole Oce-
anogr. Inst., 1988) who is interested in the analyses of bulk organic
matter and biomarkers to study paleoceanic PCO2 and the sources and
transport of organic matter in the marine environment.  I was a post-
doctoral fellow with Prof. John M. Hayes (Depts. of Geology and Chemis-
try, Indiana Univ.) where we developed a molecular isotopic technique
for the reconstruction of paleoceanic PCO2 (Nature 347:462-464).  I
continued on there as an Assistant Scientist, collaborating on downcore
and mapping studies of paleo-PCO2 in the eastern and central equato-
rial Pacific with J. Hayes, A. Fluegge, A. Mix, and F. Prahl.  I am
presently a Research Scientist/Adjunct Assistant Professor at the
Avery Point (Oceanography) Campus of the Univ. of Connecticut in
southern New England.
    The main reason that I subscribe to Isogeochem is to see "what's
going on" both technically and scientifically in stable isotopes. Des-
pite the fact I attend meetings in organic geochemistry, marine chemis-
try, and paleoeanography, it's remarkable to me to see the variety of
topics that come across the wire.
   Here's a question: What factors other than CO2(aq) concentration
and growth rate significantly affect the d13C of phytoplanktonic
Corg?  Let's specify this question only to phytoplankton that pas-
sively accept CO2(aq).

Yours Truly,
John P. Jasper

Marine Science and Technology Center/Dept. of Marine Sciences
Univ. of Connecticut
Groton,  CT   06340
203-445-3492 (Office)
203-445-3484 (Fax)