Traditional simulations of shale fracture propagation are mostly limited to two-dimensional models,and do not consider the mechanism of multi-fracture synchronous competitive propagation.Construction schemes for fracturing are mostly based on statistical analysis and field experience,which cannot effectively screen out the influence parameters of strong sensitivity in complex fracture network fracturing effects.To address this issue,a numerical model of fractured geomechanics in three-dimensional space is developed using the actual reservoir of W204H well area in the Weiyuan Block as a case study.The model takes into account the synchronous competitive propagation of fractures in multi-cluster fracturing and analyzes the impact of in-situ stress on construction parameters.Furthermore,the model quantitatively studies the influence of in-situ stress difference,cementing strength of natural fractures,perforation parameters,and fracturing fluid discharge on the volume of complex fracture networks.The results indicate that a higher in-situ stress difference leads to a lower activation probability of natural fractures and a less complex fracture network.Additionally,a lower cementation strength of natural fractures results in easier activation and capture of hydraulic fractures.When the cementation strength is less than that of the rock matrix,hydraulic fractures will penetrate natural fractures and propagate along the fracture height.Furthermore,a higher perforation combination density results in a smaller perforation pressure drop and a weaker ability to alleviate inter-cluster stress interference.The hydraulic fracture is more likely to propagate along natural fractures with an increase in the injection rate of fracturing fluid.To ensure the uniform propagation of multiple clusters when controlling dense perforation clusters,it is recommended to use large discharge and high viscosity fracturing fluid.This study provides a theoretical basis for the optimal design of volume fracturing in fractured shale reservoirs.
[1] 赵金洲,陈曦宇,李勇明,等.水平井分段多簇压裂模拟分析及射孔优化[J].石油勘探与开发,2017,44(1):117-124.
ZHAO Jinzhou,CHEN Xiyu,LI Yongming,et al.Numerical simulation of multi-stage fracturing and optimization of perforation in a horizontal well[J].Petroleum Exploration and Development,2017,44(1):117-124.
[2] 邹才能,朱如凯,董大忠,等.页岩油气科技进步、发展战略及政策建议[J].石油学报,2022,43(12):1675-1686.
ZOU Caineng,ZHU Rukai,DONG Dazhong,et al.Scientific and technological progress,development strategy and policy suggestion regarding shale oil and gas[J].Acta Petrolei Sinica,2022,43(12):1675-1686.
[3] 孙龙德,邹才能,贾爱林,等.中国致密油气发展特征与方向[J]. 石油勘探与开发,2019,46(6): 1015-1026.
SUN Longde,ZOU Caineng,JIA Ailin,et al.Development characteristics and direction of tight oil and gas in China[J].Petroleum Exploration and Development,2019,46(6):1015-1026.
[4] CHEN Z,BUNGER A P,ZHANG X,et al.Cohesive zone finite element-based modeling of hydraulic fractures[J].Acta Mechanica Solida Sinica,2009,22(5):443-452.
[5] WANG W,ZHANG K,SU Y,et al.Fracture network mapping using integrated micro-seismic events inverse with rate-transient analysis[C].IPTC19445-MS,2019:1-13.
[6] WARPINSKI N R,TEUFEL L W.Influence of geologic discontinuities on hydraulic fracture propagation[J].Journal of Petroleum Technology,1987,39(2):209-220.
[7] ZOU Y,ZHANG S,MA X,et al.Numerical investigation of hydraulic fracture network propagation in naturally fractured shale formations[J].Journal of Structural Geology,2016,84:1-13.
[8] ROUSSEL N P,SHARMA M M.Optimizing fracture spacing and sequencing in horizontal-well fracturing[J].SPE Production & Operations,2011,26(2):173-184.
[9] MANCHANDA R,SHARMA M M,HOLZHAUSER S.Time-dependent fracture-interference effects in pad wells[J].SPE Production & Operations,2014,29(4):274-287.
[10] WU R, KRESSE O,WENG X,et al.Modeling of interaction of hydraulic fractures in complex fracture networks[C].SPE152052-MS,2012:1-14.
[11] GONZALEZ M,TALEGHANI A D,OLSON J E.A cohesive model for modeling hydraulic fractures in naturally fractured formations[C].SPE173384-MS,2015:1-16.
[12] WU K,OLSON J E.Mechanisms of simultaneous hydraulic-fracture propagation from multiple perforation clusters in horizontal wells[J].SPE Journal,2016,21(3):1000-1008.
[13] EL-RABBA A M,SHAH S N,LORD D L.New perforation pressure-loss correlations for limited-entry fracturing treatments[J]. SPE Production & Facilities,1999,14(1):63-71.
[14] LIU X,QU Z,GUO T,et al.Numerical simulation of non-planar fracture propagation in multi-cluster fracturing with natural fractures based on Lattice methods[J].Engineering Fracture Mechanics,2019,220:106625.
[15] BUNGER A P,ZHANG X,JEFFREY R G.Parameters affecting the interaction among closely spaced hydraulic fractures[J].SPE Journal,2012,17(1):292-306.
[16] WANG X L,SHI F,LIU C,et al.Extended finite element simulation of fracture network propagation in formation containing frictional and cemented natural fractures[J].Journal of Natural Gas Science and Engineering,2018,50:309-324.
[17] BEHNIA M,GOSHTASBI K,MARJI M F,et al.Numerical simulation of interaction between hydraulic and natural fractures in discontinuous media[J].Acta Geotechnica,2015,10:533-546.
[18] 钟安海.含纹层陆相页岩力学参数的尺寸效应及其对压裂裂缝的影响[J].油气地质与采收率,2023,30(5):22-30.
ZHONG Anhai.Size effect of mechanical parameters of laminated continental shale and its impact on hydraulic fractures[J].Petroleum Geology & Recovery Efficiency,2023,30(5):22-30.
[19] 郭红鑫,程林松,王鹏,等.碳酸盐岩油藏不同裂缝产状岩心水驱油实验及水驱规律[J].油气地质与采收率,2022,29(6):105-112.
GUO Hongxin,CHENG Linsong,WANG Peng,et al. Water flooding experiment and law of carbonate reservoir cores with different fracture occurrences[J].Petroleum Geology & Recovery Efficiency,2022,29(6):105-112.
[20] 任岚,于志豪,赵金洲,等.深层页岩气断层属性对压裂缝网的影响[J].特种油气藏,2023,30(2):95-100.
REN Lan,YU Zhihao,ZHAO Jinzhou,et al.Influence of fault attributes of deep shale gas on fracturing fracture network[J]. Special Oil & Gas Reservoirs,2023,30(2):95-100.
[21] 于正昊,徐加祥,付颖,等.闭合压力作用下支撑剂过顶替对裂缝缝宽的影响[J].大庆石油地质与开发,2022,41(1):69-76.
YU Zhenghao,XU Jiaxiang,FU Ying,et al.Effect of proppant overdisplacing on hydraulic fracture aperture[J].Petroleum Geology & Oilfield Development in Daqing,2022,41(1):69-76.