Diffusive seep; Ground water seep; Hydrocarbon seep; Methane seep; Oil seep. The terms "seep" and "seepage" can be used as alternates
Fluid flow containing reduced compounds, e.g., methane or hydrogen sulfide (see entry Sulfur Cycle ), with almost no temperature anomalies compared with ambient seawater gushing out from or reaching very close proximity to the seafloor.
Active water circulation systems can be found at seafloor level and beneath the seafloor along the plate boundaries such as mid-ocean ridges and trenches. It is well known that at ocean ridges, hydrothermal fluid containing reduced compounds and minerals vent out from the seafloor. In contrast to the hydrothermal vents, focused flow containing reduced compounds, e.g., methane and hydrogen sulfide, gushing out from the seafloor can also be found along active and passive continental margins and around diapirs of serpentine and salt rock (halite) with no or less temperature