Significance of hydrocarbon seepage relative to petroleum generation and entrapment

To properly predict subsurface petroleum properties, interpretation of near-surface geochemical data must recognize many potential problems including recent organic matter input, transported hydrocarbons, bacterial alteration, mixing, contamination, and fractionation effects. Surface geochemical data should always be integrated with other geological data. Calibration datasets to determine the utility of near-surface geochemical techniques within particular basinal settings are essential when evaluating prospects for hydrocarbon charge.