Fatty acids diagenesis

Acids other than n-fatty acids have been shown to be important components in the mono-AME fraction, though they are generally present in much smaller concentration than in the straight-chain acids. The branched-chain acids wo-I4 0 (14 0 refers to the n-fatty acid with 14 C atoms and 0 double bonds iso-l4 0 indicates the iso isomer of 14 0), wo-I5 0, ant-I5 0, iso l7 0, and ant-I7 0 were observed to be present in most samples. As previously mentioned, branched-chain acids are often taken to be representative of a bacterial input to sediments (i, 2i, 24). Since bacteria are known to be active in assisting plant diagenesis, which leads to coalification (40), one would expect to find evidence of their presence. 

Matsuda, Hiromi. Early Diagenesis of Fatty Acids in Lacustrine Sediments—... 

Johnson, R.W. and Calder, J.A., 1973. Early diagenesis of fatty acids and hydrocarbons in a salt marsh environment. Geochim. Cosmochim. Acta, 37 1943—1955. 

Spiro B., Dinur D. and Aizenshtat Z. (1983a) Evaluation of source, environment of deposition and diagenesis of some Israeli oil shales n-alkanes, fatty acids, tetrapyrroles and kerogen. Chem. Geol. 39, 189-214. 

---