Changes

==Pressure effects==

==Pressure effects==

At pressures that exceed the critical point for hydrocarbon mixtures, the terms “gas phase” and “oil phase” become ambiguous. A single phase generally occurs at pressures above 4,000 psi and temperatures above [[temperature::200°F]] ([[temperature::93°C]]). For a hydrostatic gradient, this pressure converts to a little less than [[depth::9,000 ft]] with a geothermal gradient of about [[temperature::1.5°F]]/100 ft and a surface temperature of [[temperature::70°C]].

At pressures that exceed the critical point for hydrocarbon mixtures, the terms “gas phase” and “oil phase” become ambiguous. A single phase generally occurs at pressures above 4,000 psi and temperatures above [[temperature::200°F]] ([[temperature::93°C]]). For a hydrostatic gradient, this pressure converts to a little less than [[depth::9,000 ft]] with a [[geothermal gradient]] of about [[temperature::1.5°F]]/100 ft and a surface temperature of [[temperature::70°C]].

==Phase effects on composition==

==Phase effects on composition==