Small complex fault-block reservoirs with edge and bottom water usually feature in narrow oil-bearing belts

multiple oil layers and large stratigraphic dip and so on.Controlled by structural shape

reservoirs and interbed barrier

the driving mechanisms of edge and bottom water are complicated and have big influences on development effect

making it difficult to determine development mode.We established mathematic and numerical models based on quantification of sealing capacity of interbed barriers.Using numerical simulation

we defined development modes under different conditions of interbed barriers and oil-bearing belt width.For oil reservoirs with strong vertical sealing capacity of interbed barriers and wide oil-bearing belts

layer-by-layer or layer-subdivision production can improve oil recovery.While for oil reservoirs with narrow oil-bearing belts

cross-layer production should be avoided.Oil recovery of layer-by-layer or layer-subdivision production is higher than that of other development modes.However

layer-by-layer production may reduce production rate and separate layer production may increase investment

so commingled production would be more profitable when the oil-bearing belts are narrow.In narrow oil reservoirs

the nearer the producer is to edge water

the lower oil recovery is

so producers should be placed from edge water as far as possible.