Hi everyone,

 I'm looking at the extraction of humic and humin acids in sandy soils from
Fraser Island (Queensland) for their % content, C/N ratio and d13C.  I am
aware the extraction technique initially digests the sample in HCl.
However, the samples I am looking at come from a sandy soil.  Is it alright
to use HF following the HCl to digest as much of the silica as possible, or
will this alter the % content, C/N ratio and d13C?

 Many thanks in advance.

 Chris Turney

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Dr. Chris S.M. Turney
Research School of Earth Sciences
The Australian National University
Canberra, ACT 0200
Australia

Fax: 02 6249 0738                     Tel: (wk) 02 6249 3412
                                                (+61 2 6249 3412)
    (+61 2 6249 0738)

E-mail: [log in to unmask]



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