Archive:Petroleum seep
A seep is a wet place, where a liquid, usually groundwater, has oozed from the ground to the surface. Seeps are usually not flowing, with the liquid sourced only from underground.
The term seep may also refer to the movement of liquid hydrocarbons to the surface and between geological layers. Oil may rise from the sea floor to sea surface and can form tar balls that can wash up on beaches.
Much of the oil discovered in California during the 19th century was from seeps where oil had risen to the surface.