(from the article `petroleum production`) When a large part of the crude oil in a reservoir cannot be recovered by primary means, a method for supplying extra energy must be found. Most ...
Recovery of oil or gas from a reservoir by artificially maintaining or enhancing the reservoir pressure by injecting gas, water or other substances into the reservoir rock.
An artificial means of forcing oil out of rock by repressurizing older oil reservoirs with injections of gas or water.