延长油田水平井开发模式矿场实践

FIELD PRACTICE OF HORIZONTAL WELL DEVELOPMENT IN YANCHANG OILFIELD

延长油田位于鄂尔多斯盆地陕北斜坡和渭北隆起带,油层埋藏浅、地层能量不足,储层微观孔喉配置多样,非均质性极强,油水关系复杂,特低-超低渗储量占总探明储量的85%,开发难度大,平均单井日产油仅为0.4t,常规直井无法有效动用,复杂的油藏地质与地面条件决定了要提高油田产量与单井产能,必须采用水平井开发.针对不同类型油藏水平井开发特点,采用浅层水平井弓型轨迹控制技术,边底水差异控水绕锥技术及致密油交错缝网压裂技术,矿场实践表明,水平井开发效果显著,水平井产量是同期常规油井产量的5倍左右,且同期递减率低于常规井,大幅度提高了储量动用程度,实现了难采储量的有效开发,对国内外同类油藏开发具有重要的借鉴意义.

Yanchang oilfield is located in the northern Shaanxi slope of Ordos basin and the uplift belt of Weihe river,with shallow oil layer,insufficient formation energy,diverse reservoir microscopic pore configuration,strong heterogeneity,complex oil-water relationship,and extra-low and ultra-low permeability reserves accountingfor 85%of the total proven reserves,development is very difficult,the average single well oil production is only 0.4 t.The conventional vertical wells can’t be very effective,complex reservoir geology and surface conditions have decided that the horizontal wells must be drilled to increase single well production and whole oil field production.According to the characteristics of the different types of reservoirs,the introduction of shallow arch type horizontal well trajectory control,different edge-bottom water control and network fracturing technology in field practice shows that horizontal well development is remarkable in results,the horizontal well production is about 5 times that of the conventional oil well at the same period and decline rate lower than that of conventional well,greatly improved the reserve recovery degree.