摘要
松辽盆地仅在古龙凹陷英51井、古109井钻遇凝析气层,凝析气层下部均有含溶解气的油层,它们皆来自凹陷内青山口组高成熟源岩,用目前业已提出的凝析油气相态成因机制难以得到解释。为了解决这一问题,用相对挥发度探讨凝析气的相态成因,认为古龙凹陷凝析气是热蒸发作用形成的,发生热蒸发分馏时,油气藏中不同组分的蒸发能力不同,这种差异可用相对挥发度(α)来表征,并对此进行了实验验证,证明α是约束热蒸发形成的凝析油气与下伏残留油气组分比值关系的纽带;古龙凹陷凝析气层主要烃类组分比值与其下伏油层主要烃类组分比值之间的关系与状态方程计算的地层条件下热蒸发α保持一致,从而证实古龙凹陷的凝析气是热蒸发作用形成的。
The condensate gas reservoirs were drilled only in wells Ying-51 and Gu-109 in Gulong Sag in Songliao Basin. The lower part of the condensate gas reservoir is oil reservoir containing dissolved gas. All of them came from the high maturity source rocks of Qingshankou Formation in the sag. It is difficult to be interpreted by the phase state genetic mechanism having been proposed currently. For this reason, through analyzing the phase state genesis by use of relative volatility, it was considered the condensate gas in Gulong Sag was formed by thermal evaporation. When the thermally evaporative fractionation occurs, the thermally evaporating abilities of different components in oil and gas reservoir are distinct, which may be characterized by relative volatility (α). By means of experimental confirmation, it was proved that α is a key factor controlling the relations between component ratios of the condensation oil and gas formed by thermal evaporation and the underlying residual oil and gas; and the relation between the main hydrocarbon component ratio of the condensate gas reservoirs in Gulong Sag and that of their underlying oil reservoirs is consistent with the thermal evaporation α calculated by applying state equation under subsurface conditions, thus confirming that the condensate gas in Gulong Sad was formed by thermal evaporation.
出处
《天然气工业》
EI
CAS
CSCD
北大核心
2005年第9期4-6,9,共4页
Natural Gas Industry
基金
石油科技中青年创新基金资助(03E701)。
