A good definition of a seep is ''the surface expression of a...

A good definition of a seep is ''the surface expression of a migration pathway, along which petroleum is currently flowing, driven by buoyancy from a sub-surface origin'' (Clarke & Cleverly,1990). Knowledge of where oil and gas seeps are emerging is therefore a key piece of evidence in reducing the risk on source presence in a new basin as seeps originate by leakage from buried oil and gas accumulations. At the most basic level, this demonstrates that the basin contains a generating source rock and hence a viable petroleum system.