台北凹陷侏罗系储层次生孔隙特征及形成机理

Fundmental characteristics and formation mechanism of secondary porosity in Jurassic reservoirs in Taibei Depression,Turpan-Hami Basin

通过台北凹陷侏罗系储层岩石学特征、孔隙发育特征的分析 ,得出其原生孔隙不发育 ,次生孔隙是主要孔隙类型和油气聚集的主要空间 ,进而分析了次生孔隙的微观、宏观识别标志以及空间分布特征。通过孔隙水中有机酸和碳酸含量与来源的分析 ,探讨了次生孔隙的形成机理 ,认为有机酸对骨架颗粒长石和岩屑的溶解是形成次生孔隙的根本原因。该研究对于台北凹陷乃至整个盆地侏罗系的油气勘探和开发具有重要的现实意义。

Through analyzing the petrology characteristics, the pore type and its characteristics of Jurassic reservoirs in Taibei Depression,Turpan-Hami Basin, it was found that primary porosity is poorly developed and secondary porosity is chief pore type and chief space for oil-gas accumulation. Further, the identifying signs of secondary porosity and its distribution characteristics are analyzed. According to the contents and the origins of organic and carbonic acids in pore water, the formation mechanism of secondary porosity is disussed. The dissolution of feldspar and lithic fragment in framework grains by organic acids is the main cause forming secondary porosity. It is very important for exploration and development of oil-gas in Jurrasic in Taibei Depression or even Turupan-Hami Basin to study the fundmental characteristics and formation mechanism of secondary porosity.