We found some heavy signatures in the Tasmanian tasmanite -12 for TOC and -7
for individual compounds. This is unusual because it is marine and not
related to methanogenesis. In the paper (Geochimica et Cosmochimica Acta 58,
3803-22 1994) we attributed this to ice cover at the time of deposition and
a sample of sea ice algae gave a value of -7. More work on the effects of
ice cover has been done by Roger Summons and should be published soon.

This probably isn't relevant but you never know.....

Andy
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**                                                                        **
**          Andy Revill             Tel (002) 325278 Int. +61 02 325278   **
**       Organic Geochemist         FAX (002) 325123 Int. +61 02 325123   **
**   CSIRO Division of Oceanography                                       **
**            GPO Box 1538          e-mail [log in to unmask]     **
**               Hobart                                                   **
**             Tas. 7001                                                  **
**             Australia                                                  **
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