Oil Fingerprinting: Biomarker Identification in Oil and Sediment Samples
Biological markers (biomarkers) are compounds such as terpanes, steranes, and steroids that are derived from organisms present in the original biomass from which organic-rich sediments and oils were formed. These compounds can be measured in both oils and source rock bitumens, and they can be used to establish a correlation between an oil sample and the original petroleum source rock.
Combined gas chromatography / mass spectrometry (GC/MS) can be used to analyze for biomarkers in oil samples. However, there are numerous interferences present that have the same integer mass as biomarkers, but different elemental compositions. Because these isobaric compounds have different exact masses than the biomarkers, the interferences can be separated by high-resolution mass spectrometry. Some examples of compounds that interfere with the detection of biomarkers are given in Table I.