MOLECULAR INDICATORS OF SECONDARY OIL MIGRATION DISTANCES

The ability to determine the distance migrated by an oil from source r ock to reservoir could greatly assist in the identification of new, ec onomically viable accumulations of petroleum. Non-alkylated benzocarba zoles, which are present in trace quantities in oils, exhibit changes in both absolute and relative concentrations that correlate with migra tion distance, independent of the maturity of the oils. Such molecules appear promising as empirical-but quantitative-indicators of the rela tive migration distances of oils, and represent a first step towards t rue source-reservoir distance indicators.