Summary
The structures of the fish fossil and the diatoms were imaged in detail and these could be used for proper identification. From the difference in observed structures, it was inferred that three different types of diatoms are present in the sample and these are termed as Type 1, Type 2 and Type 3 Diatoms.
The X-Ray spectroscopy of fish produced a high Ca peak and that of the diatoms produced high Si peaks. A high peak of gold (Au) was also produced in both the cases and it was ignored since the peak came from 300 Å gold coating. The correlation of the Ca with fish bones and the Si with the diatoms was proven by the X-Ray maps. The X-Ray maps of the fish showed absence of theSi in place of bones and concentration of the Ca in the same place. The opposite thing is observed in case of both the diatoms, where the Si concentration and the Ca depletion is noticed in place of diatoms. This proved that the fossils are not altered and would be a good source of information. In terms of interaction volume both the fish and diatoms looked the same.
Diatom Rouxia californica ( Koizumi et al., 2009) and Type 2 diatom
identified as type 2 diatom here, could potentially be Rouxia californica, based on similarity of the structures (Koizumi et al., 2009). However, more work is necessary before solid inference could be drawn in identification of the diatoms and the fish.
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Acknowledgements
Many thanks to Brian Mcintyre for his help in every stage of the project. Special thanks to Donnell Jackson, Sergey Korjenevski and Nilotpal Ghosh for helping out with different problems in the lab and to Gerry Kloc for his help in the sample preparation. Lastly, I would also like to thank my advisor Carmala Garzione for her active support in the project.