塔河油田奥陶系油藏地层水赋存分布

Occurrence and distribution of formation water in the Ordovician reservoirs of the Tahe Oilfield

根据地层水赋存状态,在塔里木盆地塔河油田奥陶系油藏地层水中区分出3种不同的类型:洞穴底部油气驱替残留水、洞穴周缘小缝洞系统驱替残留水和储层下部层间水,并分析了不同类型水体的化学—动力学特征。塔河油田奥陶系油藏储层非均质性强,油水分布规律十分复杂。背景储层缝洞发育程度不同,油气驱替程度不同,储集空间大小不同,其相应的油水分布规律、油藏开发动态及含水动态都不尽相同。本文总结了这些不同点并探讨了其油气勘探意义。

According to the occurrence of formation water, three types of water were identified in the Ordovician reservoirs of the Tahe Oilfield in the Tarim Basin： 1 ） residual water in bottom of cave after oil and gas displacement, 2） residual water in fracture/pore around cave after oil and gas displacement, and 3） interlayer water below reservoirs. The chemical and dynamical characteristics of each type mentioned-above of groundwater were analyzed. Due to strong heterogeneity of the Ordovician carbonate reservoirs in Tahe, pore structures and oil-water distributions were very complicated. Because of the differences in the development of background reservoirs, displacement percentage of oil and gas, and the size of reservoirs, variations in the corresponding oil-water distribution, development performance and water cut behaviors were observed, which was summed up and their oil-gas exploration significance was discussed.