Gas-Oil Ratio (GOR)
The volume of gas produced per barrel of oil, usually in cubic feet per barrel. GOR helps classify a well as oil or gas and tracks reservoir behavior.
Gas-oil ratio, or GOR, is the volume of natural gas produced for each barrel of oil, normally expressed in cubic feet of gas per barrel. A low GOR signals an oil well, while a high ratio points to a gas well or a gas-rich reservoir. Operators and regulators use GOR thresholds to classify wells, which can affect how a well is permitted and reported.
GOR also tells a story about the reservoir over time. As reservoir pressure drops below the bubble point during a well's life, dissolved gas comes out of solution and the producing GOR often rises — a clue to how the reservoir is behaving and how it may decline. It is closely related to the well's decline curve and its overall oil-and-gas production mix.
For a mineral owner, the mix matters because oil and gas are priced and deducted differently. A shift in GOR changes the blend of oil revenue versus gas revenue feeding your royalty, which is one reason production trends are worth watching.