Hi Alice,

It is possible that "cooking" your samples could affect the organic 
matter, killing off the fresh marine organic matter and leaving 
behind resistant stuff like the terrestrial organic matter.  Thus, I 
guess it could cause the d13C to decrease in the worse case scenario. 
Why don't you throw a bit of Saanich Bulk sediment into the oven and 
do the same thing.  See if you can change the d13C and d15N.

Have fun,

>Hi All,
>This may seem like a silly question, but while I was drying down acidified
>sediment samples for d13C analysis, some of the samples appeared to be
>overbaked. The dried sediment in the centre of the bottom of the vial had
>a slightly scorched appearance whereas the sediment on the periphery
>appeared to dry ok.
>How would the d13C signature of these overcooked samples be affected, if
>at all? I know the samples get thrown into a furnace in the end, but I
>would like to know if my sample prep procedure could affect any results.
>University of Victoria

Jennifer McKay
Post-doctoral Researcher
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