Continued advances in analytical instrumentation and molecular chemistry suggest that the use of biomarkers to solve geochemical problems will continue to grow. The following discussion outlines several areas where further biomarker research is likely.

MIGRATION

Two processes appear to affect biomarker distributions during oil migration: solubilization and geochromatography. Solubilization, also called overprinting, is documented poorly, but it involves the incorporation of organic matter from rocks that are unrelated to the migrating petroleum. In most cases, solubilized materials are of lower thermal maturity than those comprising the migrating petroleum (Curiale, 2002). The contamination may become evident through the presence of immature (pre-oil window) biomarkers, such as olefins (Curiale and Frolov, 1998), or as alteration of molecular and isotopic maturation parameters. Solubilization has been observed in various areas, including the Mahakam Delta (Durand, 1983; Hoffmann et al., 1984; Jaffé et al., 1988a; Jaffé et al., 1988b), Australia (Philp and Gilbert, 1982; 1986), Cook Inlet, Alaska (Hughes and Dzou, 1995), Gulf of Mexico (Curiale and Bromley, 1996), offshore Brunei (Curiale et al., 2000), and Angola (Figure 19.1). Evidence of solubilization typically consists of mixed thermal maturity signals in the same crude oil. For example, one parameter might indicate high maturity because the compounds used for the parameter are dominant components in the migrated fraction of the oil. Another parameter might indicate lower thermal maturity because the compounds used for this parameter are dominant in the solubilized contaminants picked up by the migrating oil.