裂缝性页岩储层多级水力裂缝扩展规律研究
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摘要
水力裂缝监测技术显示页岩储层中水力裂缝形态复杂,与传统的砂岩储层有本质区别,传统的裂缝扩展模型难以描述和解释页岩地层裂缝扩展的复杂性。基于线弹性断裂力学理论,针对页岩地层裂缝发育的特征,采用位移不连续法建立了一种多裂缝扩展二维数值模型,模拟了页岩地层中水力裂缝在随机分布的天然裂缝干扰下扩展的复杂形态。数值模拟显示,当相对净压力较大、天然裂缝与初始水力裂缝最优扩展方向夹角较大时,更倾向于形成复杂形态裂缝;水平应力差较大时,水力裂缝分叉的几率越小,通过对页岩露头的真三轴水力压裂物理模拟试验研究进一步验证了数值模拟方法的合理性,龙马溪组页岩地层的微地震监测解释结果与本数值模拟结果吻合良好。
The monitoring of hydraulic fracture shows that the morphology of hydraulic fracture in shale reservoirs is complex, and is essentially different from that in the traditional sandstone reservoirs. The traditional models for fracture propagation are difficult to describe and explain the complexity of fracture propagation in shale formation. Based on the theory of linear elastic fracture mechanics, in accordance with fracture development characteristics in shale formation, a 2D numerical model for multi-fracture propagation is established by adopting the displacement discontinuity method. This model simulates the complex morphology of hydraulic fracture propagation under the interference of randomly distributed natural fractures in shale formation. Numerical simulations show that when the relative net pressure is high, the angle between natural fracture and optimized propagation direction of the initial hydraulic fracture is large, and it is more liable to create complicated fractures. And when horizontal stress difference is larger, it is less liable for hydraulic fractures to branch. The true tri-axial hydraulic fracturing tests on shale outcrops further validate the reasonability of this numerical simulation method. The results of micro seismic monitoring interpretation of Longmaxi shale formation agree well with the numerical results in this paper.
The monitoring of hydraulic fracture shows that the morphology of hydraulic fracture in shale reservoirs is complex, and is essentially different from that in the traditional sandstone reservoirs. The traditional models for fracture propagation are difficult to describe and explain the complexity of fracture propagation in shale formation. Based on the theory of linear elastic fracture mechanics, in accordance with fracture development characteristics in shale formation, a 2D numerical model for multi-fracture propagation is established by adopting the displacement discontinuity method. This model simulates the complex morphology of hydraulic fracture propagation under the interference of randomly distributed natural fractures in shale formation. Numerical simulations show that when the relative net pressure is high, the angle between natural fracture and optimized propagation direction of the initial hydraulic fracture is large, and it is more liable to create complicated fractures. And when horizontal stress difference is larger, it is less liable for hydraulic fractures to branch. The true tri-axial hydraulic fracturing tests on shale outcrops further validate the reasonability of this numerical simulation method. The results of micro seismic monitoring interpretation of Longmaxi shale formation agree well with the numerical results in this paper.
引文
[1]周健,陈勉,金衍,等.裂缝性储层水力裂缝扩展机理试验研究[J].石油学报,2007,28(5):109–113.(ZHOU Jian,CHEN Mian,JIN Yan,et al.Experimental study on propagation mechanism of hydraulic fracture in naturally fractured reservoir[J].Acta Petrolei Sinica,2007,28(5):109–113.(in Chinese))
[2]侯冰,陈勉,程万,等.页岩气储层变排量压裂的造缝机制[J].岩土工程学报.2014,36(11):2149–2152.(HOU Bing,CHEN Mian,CHENG Wan,et al.Fracture mechanism on shale gas reservoir fracturing with variable pump rate[J].Chinese Journal of Geotechnical Engineering.2014,36(11):2149–2152.(in Chinese))
[3]CHENG W,JIN Y,CHEN M,et al.A criterion for identifying hydraulic fractures crossing natural fractures in 3D space[J].Petroleum Exploration and development,2014,41(3):371–376.
[4]衡帅,杨春和,曾义金,等.页岩水力压裂裂缝形态的试验研究[J].岩土工程学报,2014,36(7):1243–1251.(HENG Shuai,YANG Chun-he,ZENG yi-jin,et al.Experimental study on hydraulic fracture geometry of shale[J].Chinese Journal of Geotechnical Engineering,2014,36(7):1243–1251.(in Chinese))
[5]KESHAVARZI R,JAHANBAKHSHI R.Real-time prediction of complex hydraulic fracture behaviour in unconventional naturally fractured reservoirs[C]//Society of Petroleum Engineers Unconventional Gas Conference and Exhibition.Muscat,2013.
[6]赵海峰,陈勉,金衍,等.页岩气藏网状裂缝系统的岩石断裂动力学[J].石油勘探与开发,2012,39(4):465–470.(ZHAO Hai-feng,CHEN Mian,JIN Yan,et al.Rock fracture kinetics of the fracture mesh system in shale gas reservoirs[J].Petroleum Exploration and Development,2012,39(4):465–470.(in Chinese))
[7]陈勉.页岩气储层水力裂缝转向扩展机制[J].中国石油大学学报(自然科学版),2013,37(5):88–94.(CHEN Mian.Re-orientation and propagation of hydraulic fractures in shale gas reservoir[J].Journal of China University of Petroleum,2013,37(5):88–94.(in Chinese))
[8]WENG X W,KRESSE O,COHEN C E,et al.Modeling of hydraulic fracture network propagation in a naturally fractured formation[C]//Society of Petroleum Engineers Hydraulic Fracturing Technology Conference,24-26 Woodlands,2011.
[9]KRESSE O,COHEN C,WENG X,et al.Numerical modeling of hydraulic fracturing in naturally fractured formations[C]//The 45th U.S.Rock Mechanics Symposium,San Francisco,2011.
[10]RAHMAN M.A fully coupled numerical poroelastic model to investigate interaction between induced hydraulic fracture and pre-existing natural fracture in a naturally fractured reservoir:Potential application in tight gas and geothermal reservoirs[C]//The Society of Petroleum Engineers Annual Technical Conference and Exhibition.New Orleans,2009.
[11]RAHMAN M,AGHIGHI M,RAHMAN S,et al.Interaction between induced hydraulic fracture and pre-existing natural fracture in a poro-elastic environment:effect of pore pressure change and the orientation of natural fracture[C]//The Asia Pacific Oil and Gas Conference&Exhibition,Jakarta,2009.
[12]KRESSE O,WENG X,GU H,et al.Numerical modeling of hydraulic fractures interaction in complex naturally fractured formations[J].Rock Mechanics and Rock Engineering,2013,46(3):555–568.
[13]WU R,KRESSE O,WENG X W,et al.Modeling of interaction of hydraulic fractures in complex fracture networks[C]//The Society of Petroleum Engineers Hydraulic Fracturing Technology Conference.Woodlands,2012.
[14]王伯军,张士诚,张劲.斜井水力压裂过程中的缝间干扰力学机理研究[J].岩土工程学报,2009,31(2):203–206.(WANG Bo-jun,ZHANG Shi-cheng,ZHANG Jin.Mechanism of crack interaction in hydraulic fracture of inclined wells[J].Chinese Journal of Geotechnical Engineering,2009,31(2):203–206.(in Chinese))
[15]TALEGHANI A D,OLSON J E.Nuermerical modeling of multistranded-hydraulic fracture propagation:accounting for the interaction between induced and natural fractures[J].SPE Journal,2009,16(3):575–581.
[16]KESHAVARZI R,MOHAMMADI S,BAYESTEH H.Hydraulic fracture propagation in unconventional reservoirs:the role of natural fractures[C]//46th U.S.Rock Mechanics/Geomechanics Symposium.Chicago,2012.
[2]侯冰,陈勉,程万,等.页岩气储层变排量压裂的造缝机制[J].岩土工程学报.2014,36(11):2149–2152.(HOU Bing,CHEN Mian,CHENG Wan,et al.Fracture mechanism on shale gas reservoir fracturing with variable pump rate[J].Chinese Journal of Geotechnical Engineering.2014,36(11):2149–2152.(in Chinese))
[3]CHENG W,JIN Y,CHEN M,et al.A criterion for identifying hydraulic fractures crossing natural fractures in 3D space[J].Petroleum Exploration and development,2014,41(3):371–376.
[4]衡帅,杨春和,曾义金,等.页岩水力压裂裂缝形态的试验研究[J].岩土工程学报,2014,36(7):1243–1251.(HENG Shuai,YANG Chun-he,ZENG yi-jin,et al.Experimental study on hydraulic fracture geometry of shale[J].Chinese Journal of Geotechnical Engineering,2014,36(7):1243–1251.(in Chinese))
[5]KESHAVARZI R,JAHANBAKHSHI R.Real-time prediction of complex hydraulic fracture behaviour in unconventional naturally fractured reservoirs[C]//Society of Petroleum Engineers Unconventional Gas Conference and Exhibition.Muscat,2013.
[6]赵海峰,陈勉,金衍,等.页岩气藏网状裂缝系统的岩石断裂动力学[J].石油勘探与开发,2012,39(4):465–470.(ZHAO Hai-feng,CHEN Mian,JIN Yan,et al.Rock fracture kinetics of the fracture mesh system in shale gas reservoirs[J].Petroleum Exploration and Development,2012,39(4):465–470.(in Chinese))
[7]陈勉.页岩气储层水力裂缝转向扩展机制[J].中国石油大学学报(自然科学版),2013,37(5):88–94.(CHEN Mian.Re-orientation and propagation of hydraulic fractures in shale gas reservoir[J].Journal of China University of Petroleum,2013,37(5):88–94.(in Chinese))
[8]WENG X W,KRESSE O,COHEN C E,et al.Modeling of hydraulic fracture network propagation in a naturally fractured formation[C]//Society of Petroleum Engineers Hydraulic Fracturing Technology Conference,24-26 Woodlands,2011.
[9]KRESSE O,COHEN C,WENG X,et al.Numerical modeling of hydraulic fracturing in naturally fractured formations[C]//The 45th U.S.Rock Mechanics Symposium,San Francisco,2011.
[10]RAHMAN M.A fully coupled numerical poroelastic model to investigate interaction between induced hydraulic fracture and pre-existing natural fracture in a naturally fractured reservoir:Potential application in tight gas and geothermal reservoirs[C]//The Society of Petroleum Engineers Annual Technical Conference and Exhibition.New Orleans,2009.
[11]RAHMAN M,AGHIGHI M,RAHMAN S,et al.Interaction between induced hydraulic fracture and pre-existing natural fracture in a poro-elastic environment:effect of pore pressure change and the orientation of natural fracture[C]//The Asia Pacific Oil and Gas Conference&Exhibition,Jakarta,2009.
[12]KRESSE O,WENG X,GU H,et al.Numerical modeling of hydraulic fractures interaction in complex naturally fractured formations[J].Rock Mechanics and Rock Engineering,2013,46(3):555–568.
[13]WU R,KRESSE O,WENG X W,et al.Modeling of interaction of hydraulic fractures in complex fracture networks[C]//The Society of Petroleum Engineers Hydraulic Fracturing Technology Conference.Woodlands,2012.
[14]王伯军,张士诚,张劲.斜井水力压裂过程中的缝间干扰力学机理研究[J].岩土工程学报,2009,31(2):203–206.(WANG Bo-jun,ZHANG Shi-cheng,ZHANG Jin.Mechanism of crack interaction in hydraulic fracture of inclined wells[J].Chinese Journal of Geotechnical Engineering,2009,31(2):203–206.(in Chinese))
[15]TALEGHANI A D,OLSON J E.Nuermerical modeling of multistranded-hydraulic fracture propagation:accounting for the interaction between induced and natural fractures[J].SPE Journal,2009,16(3):575–581.
[16]KESHAVARZI R,MOHAMMADI S,BAYESTEH H.Hydraulic fracture propagation in unconventional reservoirs:the role of natural fractures[C]//46th U.S.Rock Mechanics/Geomechanics Symposium.Chicago,2012.
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