[[:file:oiloil-and-oilsource-rock-correlations_fig8-23.png|Figure 1]] shows m/z 217 mass fragmentograms from two oils showing quite different distributions of regular steranes. The top example is dominated by C<sub>29</sub> steranes with only moderate amounts of C<sub>27</sub> and C<sub>28</sub>. The bottom sample, in contrast, shows similar amounts of all three homologs plus moderate amounts of the C<sub>30</sub> steranes (four unlabeled peaks to the far right). | [[:file:oiloil-and-oilsource-rock-correlations_fig8-23.png|Figure 1]] shows m/z 217 mass fragmentograms from two oils showing quite different distributions of regular steranes. The top example is dominated by C<sub>29</sub> steranes with only moderate amounts of C<sub>27</sub> and C<sub>28</sub>. The bottom sample, in contrast, shows similar amounts of all three homologs plus moderate amounts of the C<sub>30</sub> steranes (four unlabeled peaks to the far right). |