Y. Huang,

You might check with some of the isotopers at theUniversity of Utah or
Brigham Young University. Years ago, I ran isotopic analyses for water from
the northwest part of the
Great Salt Lake and got some 'funny' results. The  the whole lake is a
large drying pond.
With the draught in Florida you probably have similar evaporative
fractionation occuring.

Good luck.

G. Martin




                    Yongsong Huang
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                    Sent by: Stable         Subject:     Delta D of lake
                    Isotope                 water
                    Geochemistry
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                    04/28/01 09:18
                    PM
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                    Isotope
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Dear all,

I use TC/EA coupled with Delta plus XL to run lake water samples. I am
getting good precision (< +/- 1 per mil) with He dilution. The measured
delta D has an offset from the real value, but VSMOW, GISP and SLAP plot on
a near perfect straight line with r2 = 0.9996. I use the line for isotope
correction.

However, several of my Florida lakes, after isotope correction, have delta
D values nearly +24 per mil (e.g., ocean Pond, Weir Lake). The water was
collected early September, last year. Evaporation should be significant in
the region.

Has any one analyzed delta D values (or delta 18O) for these lakes before?
Are there any literature data? Many thanks


Yongsong


Dr. Yongsong Huang
Assistant Professor
Department of Geological Sciences, Office 147
Brown University
Providence, RI02912

Tel: (401) 863-3822     Fax: (401) 863-2058
Web site: http://www.geo.brown.edu/faculty/huang/index.html