准噶尔盆地玛湖凹陷百口泉组储层水平井压裂效果地质影响因素研究

Analysis of Geological Factors Affecting Fracturing Effect of Horizontal Wells in Baikouquan Formation, Mahu Sag, Junggar Basin

摘要: 准噶尔盆地玛湖凹陷三叠系百口泉组碎屑岩储层非均质极强，影响了储层压裂改造，严重制约了石油的高效开发。选取玛湖凹陷百口泉组一段的储层样品，应用岩屑数字化技术，建立储层岩石物理模型，结合射孔冲蚀面积，重点分析研究百口泉组储层压裂效果影响因素。结果表明：1) 百一段储层矿物组成以石英、钠长石和伊蒙混层为主，储层非均质性较强，储层平面孔隙度普遍小于5%，孔隙类型主要以粒间孔和长石粒内孔为主，同时发育有大量孔隙；2) 根据储层矿物成分、孔隙结构建立岩石物理模型，并利用测井声波进行校准，结果表明百一段内储层岩石物理参数变化大；3) 射孔冲蚀面积与储层脆性参数、裂隙发育成正相关关系。脆性参数越好、裂隙越发育，进液量越大，压裂效果越好。本研究对玛湖地区百口泉组碎屑岩储层压裂改造，具有重要的指导及参考借鉴意义。

Abstract: The Triassic Baikouquan Formation clastic rock reservoir in Mahu Sag of Junggar Basin is highly heterogeneous, which affects the reservoir fracturing and severely restricts the efficient development of oil. We select the reservoir samples of the first member of Baikouquan Formation in Mahu Depression, apply the digital technology of rock cuttings, establish the reservoir rock physical model, combine the perforation erosion area, and focus on analyzing and studying the factors affecting the fracturing effect of Baikouquan Formation reservoir. The results show that: 1) The mineral composition of Baiyi Member reservoir is mainly composed of quartz, albite and Yimeng mixed layer, the reservoir heterogeneity is strong, the reservoir plane porosity is generally less than 5%, the pore type is mainly intergranular pore and feldspar intragranular pore, and a large number of pores are developed at the same time; 2) The petrophysical model is established according to the mineral composition and pore structure of the reservoir, and calibrated by logging acoustic wave. The results show that the petrophysical parameters of the reservoir vary greatly in the Baiyi section; 3) Perforation erosion area has a positive correlation with reservoir brittleness parameters and fracture development. The better the brittleness parameter, the more developed the fracture, the greater the fluid inflow, and the better the fracturing effect. This study has important guidance and reference significance for fracturing and reconstruction of Baikouquan Formation clastic rock reservoir in Mahu area.