An anomaly that occurs as a ring around a feature, such as electrical or geochemical rings around hydrocarbon accumulations.
High-pressure Air Injection
An enhanced oil recovery process utilizing compressed air that is injected into a reservoir. Oxygen in the gas reacts exothermically with the oil, producing highly mobile flue gas. The flue gas advances ahead of the reaction front and creates an efficient displacement of the in situ oil. The high displacement efficiency of high-pressure air injection is due to a combination of processes that include immiscible gas displacement, improved miscibility caused by the presence of CO2 in the flue gas, reduction in interfacial tension, oil swelling and reservoir repressurization. The process is normally used for deep, tight, light-oil reservoirs where the ability of water injection is low.
Circulation of heated fluid, usually oil, to dissolve or dislodge deposits from the production tubing. Such deposits tend to occur where a large variation in temperature is created across the entire producing system.
A compound containing only the elements hydrogen and carbon. It can exist as a solid,liquid or a gas. This term is mainly used in a catch-all sense for oil, gas and condensate.