Contingent resources are not to be confused with oil and gas reserves. They are quantities of petroleum that are estimated to be potentially recoverable from known accumulations using established technology or technology under development, but are not commercially recoverable due to certain contingencies, including economic, legal, environmental, political or other factors. It is also appropriate to classify estimated discovered recoverable quantities of oil or gas associated with projects in early evaluation stages as contingent resources. A best estimate is one where there is an equal likelihood that the actual remaining quantities of contingent resources will be greater or less that the best estimate.
In a crude oil waterflood play, water is injected into the producing reserve formation to supplement the original reservoir pressure and provide a drive mechanism to move additional oil to the producing well. Pressure maintenance and the production of oil from water injection can result in a production profile with more predictable and stable declines and higher recovery of reserve assets.
An oil recovery method that reduces residual oil saturated within the reservoir and improves the efficiency of a waterflood. Examples include polymer or CO2 floods.
An oil recovery method that optimizes the performance of a waterflood through sweep, pattern or voidage improvements. Examples include converting vertical producing wells to water injection wells or horizontal multi-stage frac drilling in traditional waterflood reservoirs.
Liquids obtained during natural gas production, including ethane, propane, butanes and condensate.
Reserve Life Index is calculated by dividing year end reserves by expected annual production.
Natural gas that is trapped within fine grained sedimentary rock known as shale. Shale gas formations are very fine-grained rocks which can contain large volumes of natural gas difficult to produce using conventional techniques. Production of natural gas from these formations typically involves complex wells, often horizontals, and large scale hydraulic fracturing which creates pathways in the rock allowing the natural gas to flow to surface.
Tight oil reservoirs have extremely low permeability where multi-stage fractured horizontal wells are needed to economically develop the property. The Bakken play in Canada and the U.S. is a good example of a tight oil reservoir that is now economic to drill due to advancements in drilling and fracing technology.