摘要
Oil-water distribution pattern is complex in Chang 9 oil reservoir of Jiyuan area,Ordos Basin.Most of Oil wells produce water in high percentage during oil test.For single well oil-water coexistence is the dominant distribution pattern.Oil-water distribution control factors were analyzed on basis of the formation water nature,oil reservoir pressure and fluid units,sand connectivity,remnant oil saturation and condition of preservation etc.Research shows that: there are multiple units in the oil reservoirs.In the same fluid unit,the connected sands contain oil to the updip direction and water to downdip direction.Relatively independent oil-water interface exists between different fluid units.Hydrocarbon charge is in lower degree in Chang 9 reservoir that leads to the complex oil-water distribution pattern.