斜井多段压裂在致密砂岩储层中的应用

合水长6油藏储层渗透率0.23 mD、孔隙度10.4％,是典型的致密砂岩油藏,隔夹层厚度较小,应力差仅2.8 MPa,压裂改造难度大,常规压裂改造受限,储层改造不充分,投产后单井产能低.在充分研究油井自身条件及裂缝扩展规律的前提下,提出利用定向井具有一定的井斜和方位角,在油层内与最大主应力方向成一定夹角,通过优化压裂施工参数,利用斜井多段压裂在层内形成多条独立裂缝,实现储层充分改造,扩大油井泄流体积,提高单井产量.

Application of Multi-interval Fracturing Technique in Dense Sandstone Reservoirs

Heshui Chang 6 reservoir(permeability 0.23 mD,porosity 10.4%)is typical tight sandstone oil reservoir,interlayer thickness is small,the stress difference is only 2.8 MPa,fracturing difficulty is big,conventional fracturing is limited,reservoir transformation is not full,single well production is low.In this paper,based on studying oil well conditions and crack propagation rule,the directional well with a certain inclination and azimuth was adopted,the directional well in reservoir formed a certain angle with the direction of the maximum principal stress;Through optimizing the fracturing parameters and using inclined multi-interval fracturing technique,independent cracks in the layer were formed,full transformation of the reservoir was realized to expand oil discharge volume and improve the yield of single well.