The sample represents organic material comprised mainly of straight-chain lipid components that yield suites of a homologous series of pyrolysis products, notably the long-chain alkenes (Fig. F1) that are possibly derived from the breakdown of bound fatty acids that are a common component of algal biomass. In addition, there is a separate small suite of pyrolysis products comprising longer chain (C30) cyclic and branched alkenes (also biological in origin), possibly squalene derivatives. Mass chromatograms for triterpanes, m/z 191 and steranes, m/z 217 (Fig. F2A, F2B, respectively) show distributions that are not typical of hydrocarbons derived from petroleum (Fig. F2C, F2D, respectively). Additionally, the m/z 91 mass chromatogram for a petroleum from a Kazakhstan well (Fig. F3A) shows the regular distributions of n-alkanes commonly associated with oil-derived hydrocarbons. A mass chromatogram for m/z 91 for Sample 172-1063B-38X-5, 40-50 cm, however, does not show this regular distribution (Fig. F3B) and is, therefore, considered to be nonrelated to mature petroleum. Minute traces of longer chain n-alkanes are present but are insignificant when compared to the bulk of the pyrolysis products. Evidence for a series of nitrogen-bearing compounds as shown by the 115 (Fig. F4A) and 117 ions (Fig. F4B) possibly indicate the presence of proteins that may be biologically derived. The total ion current clearly shows the presence of a significant amount of contaminant, identified as silicone material on the basis of the prominent m/z 207 and 281 ions (not shown).