莺歌海盆地浅层凝析油研究

STUDY ON SHALLOW-LAYER CONDENSATES IN YINGGEHAI BASIN

采用GC/MS,GC/MS/MS技术对莺歌海盆地浅层凝析油进行了检测,除未成熟—低成熟凝析油外,发现了成熟—高成熟凝析油。根据凝析油的生物标志物分布特征进行了凝析油的类型划分及油源对比研究,确认未成熟—低成熟凝析油来自浅层(1000～3000 m)莺黄组源岩,其成因机制与CO_2对储集层的抽提作用密切相关;而成熟—高成熟凝析油可能来源于盆地深部的海相和中深湖相烃源岩。

The condensates from shallow layer in Yinggehai Basin are detected by GC/MS and GC/MS/MS technique. In addition to immature-low mature condensates, mature and high-mature condensates are discovered also. Condensates classification and oil/source correlation study were carried out on the basis of distribution characteristics of biomarkers. Results show that the immature and lowmature condensates are originated from the source rock of shallow Yinghuang Formation (1000～3000m). Their genetic mechanism is closely related to the extraction of CO_2 on reservoir. But mature-high mature condensates can be from different source rocks including marine facies in deep part of the basin and lacustrine facies of the middle part of the basin.