The oilfield in the south of Daqing Changyuan characterizes the narrow sand body most of which distributes in the shape of straps or net structures.

• 大庆长垣南部窄小砂体油田,砂体多呈条带状或枝网状分布,油层层内层间非均质较严重,在目前的高含水期,采用常规的水驱开采方法很难挖潜。