古109井凝析气藏油气特征及其形成条件分析

ANALYSIS OF OIL-GAS FORMATION & ITSCHARACTERISTICS IN GU-109 WELL

本文指出在古109井凝析气藏的气体组分中, 除了含有大量甲烷外,戊烷以后的烃类组分含量也较一般气田高,这些组分在地层条件下,逆蒸发为气体,在压力和温度下降后,又反凝析为油。凝析油的主要成分是汽油和煤油,质轻而纯净。分析了形成凝析气藏的首要条件是该井位于最有利生油区,有机质处于高成熟阶段,在一定的温度和压力条件下,液态烃开始裂解形成轻烃类,在特定的条件下转化为凝析气藏。同时指出,凝析气藏的有利勘探区在古龙凹陷内及其两侧斜坡上的断裂带、砂岩透镜体、浊积砂体和上倾尖灭的砂体中。

<ABSTRACT> The article shows that high alkyl hydrocarbons, such as pentane contained in Gu-109 well located in Gulong depression, are more than those in conventional gas-field, besides a lot of methanes. These componets componets are converted into gas under in-situ back-vaporization, and they are condensed oils after decreasing temperature-pressure. The condensales consist mainly of lighter net gasoline or Kerosenc. The favorable source area>drilled Gu-109 well, is im portant repuirement of forming the condensate pool. Under the specific con ditions organic matter is high mature stage, liquid hydrocarbons begin pyrolyzing to form light ones, or condensale pool. Also, This indicates that prospective area just is locatedin Gulong depression & its fartured zone of both flank slope, lenticular sands, turbidite sands and updip wedge-belt of sands.