鄂尔多斯盆地致密油藏水平井体积压裂开采方法探讨

Discussion on volume fracturing method of horizontal wells in tight reservoir of Ordos Basin

鄂尔多斯盆地致密油资源丰富,具有广阔的勘探开发前景,其油藏特点适合采用水平井体积压裂的方法开采。当采用水平井体积压裂法开采致密油藏时,与直井相比,初期单井产量高,增产倍数大,但是水平井见水后随着含水率上升,水平井产量递减较快,稳产的难度增大。通过矿场试验及数值模拟方法对水平井见水后的有效开采方法进行了论证:当采用水平井体积压裂法开采致密油藏时,水平井见水后通过腰部水井的温和注水、周期注水或周期采油可以明显提高单井产量、降低油井含水率,明显提高采出程度。所得结论可以为水平井体积压裂法开采致密油藏提供一定的理论参考。

The tight oil resources in Ordos Basin are abundant and have broad prospects for the exploration and development. The reservoir characteristics are suitable to exploit through the volume fracturing method of the horizontal wells. The early production of wells is high and the production increase is large when using the method to exploit tight reservoir, but the production declines rapid- ly as soon as the injected water is flowed to the bottom of the horizontal wells, so it is difficult to stable the yield. The effective mining method is discussed through the field test and numerical simulation method. When the horizontal well is used to exploit tight oil reservoir through the volume fracturing method, once the injected water is flowed to the bottom of horizontal wells, reducing the water injection of water wells of waist, the cyclic injection or the cyclic production can effectively improve the yield of single wells, reduce the water cut of oil well and increase the oil recovery. The conclusion obtained in the paper offer a certain theoretical reference to exploit the tight reservoir effectively through the volume fracturing method.