简答题 翻译：Crude petroleum is not an equilibrium mixture, and on a geological time scale its composition is slowly changing.

问答题翻译：The producing gas-oil R is the radio of the volumetric gas production rate to the volumetric oil production rate, both at surface.

问答题翻译：The gas saturation is obtained in the same manner as the retort.

问答题翻译：These reservoirs can be classified according to rock types, depending on variations in source rock, transport distance, and depositional environment.

问答题翻译：Classification of traps logically falls into three broad general groups: (1) structural, (2)stratigraphic, and (3)combination.

问答题翻译：The retort method has several disadvantages as far as commercial work is concerned.