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  | isbn    = 0-89181-602-X

  | isbn    = 0-89181-602-X

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The presence of hydrocarbon macroseeps or microseeps in the area of a geochemical survey is direct evidence that petroleum has been generated. Hydrocarbon seepage at the surface represents the end of a petroleum migration pathway. These hydrocarbons may represent hydrocarbon leakage from an [[accumulation]] or leakage along a carrier bed or other migration pathway. Anomalies defined by multiple samples from one or more survey lines may indicate the location of discrete structural or stratigraphic targets within the survey area.

The presence of hydrocarbon macroseeps or microseeps in the area of a geochemical survey is direct evidence that petroleum has been generated. Hydrocarbon seepage at the surface represents the end of a petroleum [[migration pathway]]. These hydrocarbons may represent hydrocarbon leakage from an [[accumulation]] or leakage along a carrier bed or other migration pathway. Anomalies defined by multiple samples from one or more survey lines may indicate the location of discrete structural or stratigraphic targets within the survey area.

==Anomalies and vertical migration==

==Anomalies and vertical migration==