裂缝对鄂尔多斯盆地陇东地区长7致密岩心水驱渗流特征的影响

发布时间：2019-07-12 12:22

【摘要】：在分析鄂尔多斯盆地长7天然裂缝和体积压裂人工裂缝特征的基础上,采用等效处理岩心实验法探索裂缝对长7致密岩心水驱渗流特征的影响。实验结果表明:不论是以基质渗流或者以裂缝渗流为主的岩心,油相相对渗透率都呈现出靠椅型相渗曲线特征;同时随着裂缝与基质渗透率级差和驱替压差的增大,与基质渗流为主的岩心相比,裂缝岩心渗透率曲线等渗点左移,油水相渗透率增大,但两相共流区变窄,含水上升加快,残余油饱和度升高。在同一驱替压差下,随着裂缝与基质渗透率级差的增大,致密岩心水驱油具有低含水时间短,见水后含水上升快的特征。随着驱替压差增大,以基质渗流为主的岩心,见水提前,但无水期驱油效率和最终驱油效率都增大;以裂缝渗流为主的岩心,见水提前,无水期驱油效率和最终驱油效率都降低。
[Abstract]:On the basis of analyzing the characteristics of Chang 7 natural fracture and volume fracturing artificial fracture in Ordos Basin, the influence of fracture on water flooding seepage characteristics of Chang 7 tight core is explored by equivalent treatment core experiment method. The experimental results show that the relative permeability of oil phase shows the characteristics of chair phase permeability curve, whether it is based on matrix seepage or fracture seepage. At the same time, with the increase of permeability grade difference and displacement pressure difference between fracture and matrix, compared with the core dominated by matrix seepage, the permeability curve of fracture core moves to the left and the permeability of oil-water phase increases, but the two-phase confluence zone narrows, the water content rises faster and the residual oil saturation increases. Under the same displacement pressure difference, with the increase of permeability difference between fracture and matrix, the water flooding in dense core has the characteristics of short water cut time and fast water cut rise after seeing water. With the increase of displacement pressure difference, the core with matrix seepage is ahead of time, but the oil displacement efficiency and final displacement efficiency in anhydrous period are increased, while in the core with fracture seepage, the oil displacement efficiency and final displacement efficiency in anhydrous period are decreased.
【作者单位】：长庆油田公司勘探开发研究院;低渗透油气田勘探开发国家工程实验室;
【基金】：国家科技重大专项“鄂尔多斯盆地致密油开发示范工程”(2017ZX05069)
【分类号】：TE312

【相似文献】