FWIW,
We've measured d13C of DIC in coalbed waters that are nearly as high
as 25 per mill. We've also measured silica-replaced root casts from
an evaporative lake setting >40 per mill d18O.
--
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Steve Nelson
Dept. of Geology
S389 ESC
Brigham Young University
Provo. Utah 84602
voice: 1-801-422-8688
lab: 1-801-422-5124
FAX: 1-801-422-0267
CARPE CARP: seize the fish
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