Study on Consistency of Diagnostic Ratios of Different Oils

Using GC/MS analysis means, distribution of n-alkanes, PAHs, and biomarkers and consistency of diagnostic ratios of different kinds of oil were studied. The results indicate that: (1) Some diagnostic ratios of different oils are not obviously different and may even be consistent. These diagnostic ratios include two n-alkanes diagnostic ratios ((C₁₉+C₂₀)/(C₁₉∼C₂₂) and CPI), four terpanes diagnostic ratios (C₃₁hopaneαβ(S/(S+R))∼C₃₄hopaneαβ(S/(S+R))) and one steranes diagnostic ratio (C₂₉ααα(S/(S+R))). (2) PAHs diagnostic ratios of different oils appear obviously different and it is no need to consider their consistency. (3) In addition to the stability of diagnostic ratios of different oils, their consistency of diagnostic ratios is very important in oil spill identification.