Definition - What does Reservoir Temperature mean?
Reservoir Temperature is the average temperature maintained inside a hydrocarbon reservoir. The hydrocarbons that are stored in the reservoir also have the same temperature. The temperature can be recorded with the help of a bottom hole temperature recorder during pressure testing or drill stem testing. The range of reservoir temperature may vary depending on the depth at which a particular reservoir is found.
Petropedia explains Reservoir Temperature
Reservoir temperature is primarily governed by various factors such as, its closeness to the mantle of the earth, i.e., if the depth of the hydrocarbon reservoir from the earth crust is more, the temperature and pressure is also more. Also, if the depth is more the relative heat exchange capacity and thermal conductivity is higher.
Based on these factors, one can say that the geothermal gradient of a reservoir varies based on its proximity to the earth's mantle. Geothermal gradient of a reservoir can be defined as the rate of change of temperature of a reservoir as the proximity of the reservoir increases with the earth’s mantle. On a general note, the geothermal gradient of any hydrocarbon producing area ranges from 0.6 to 1.6 degree Fahrenheit per 100 feet of increase in depth.