# Reservoir Temperature (T)

The reservoir temperature represents the temperature of the formation. It increases with reservoir depth and differs widely depending on the reservoir location's geothermal gradient.

In the analysis of gas wells, the reservoir temperature is used directly in the pressure transient analysis calculations, as well as calculating all the gas fluid properties such as gas formation volume factor (Bg), gas viscosity (mg), and gas compressibility (cg). For gas wells, the reservoir temperature has only a weak effect on the pressure transient analysis calculations.

In the analysis of oil wells, the reservoir temperature does not enter into the pressure transient analysis equations, directly, but rather It is used in calculating the oil fluid properties such as oil formation volume factor (Bo), oil viscosity (mo), oil compressibility (co), and solution gas-oil ratio (Rs). It also enters into the calculation of the total reservoir fluid rate (qtBt) through the gas formation volume factor (Bg), and in the calculation of total compressibility (ct) through the calculation of gas compressibility (cg).