天然气工业2025，Vol.45Issue(4)：121-132,12.DOI:10.3787/j.issn.1000-0976.2025.04.010
泥(页)岩地层漏失诱导裂缝扩展机制及裂缝宽度预测
Mechanisms of lost circulation induced fracture propagation and fracture width prediction in shale reservoirs
摘要
Abstract
In the process of reservoir drilling,lost circulation can cause serious economic losses and safety hazards.Clarifying the mechanisms and influential factors of lost circulation induced fracture propagation is of great and practical significance to the prevention and control of lost circulation in shale reservoirs.In this paper,the fluid pressure distribution within fractures is solved by using the tri-porosity medium flow model of mud cake,lost circulation material and matrix.Then,according to the dislocation fracture mechanics theory,fracture width and stress intensity factor are calculated by the semi-analytic method,and the fracture propagation mechanisms are investigated.Finally,the change of fracture width is predicted.The following results are obtained.First,the permeability of lost circulation material is the main factor of influencing the fluid flow within fractures in shale reservoirs.The plugging of lost circulation material can effectively reduce the loss,retard the pressure transmission at the fracture tips,and delay the time of stress intensity factor to reach the critical fracture toughness,so as to inhibit fracture propagation.Second,fracture width is positively correlated with lost circulation material permeability,wellbore pressure and stress anisotropy,and negatively correlated with fluid viscosity,elastic modulus and Poisson's ratio.Third,hydration can weaken the fracture toughness,reduce leakage pressure,and thus promote fracture propagation.Fourth,in order to inhibit fracture propagation and improve the success rate of one-trip plugging,it is necessary to decrease the permeability of lost circulation material,increase the viscosity of drilling fluid,inhibit the hydration swelling of shale,and select reasonable wellbore pressure and particle size of lost circulation material matching fracture width.The research results reveal the mechanisms of fracture propagation in shale reservoirs,and provide a theoretical basis for the control of wellbore pressure and the selection and design of lost circulation materials in leaky formations.关键词
泥(页)岩/钻井液漏失/裂缝扩展/裂缝宽度/孔隙流体流动/位错断裂力学/水化作用/堵漏材料Key words
Shale/Lost circulation/Fracture propagation/Fracture width/Pore fluid flow/Dislocation fracture mechanics/Hydration/Lost circulation material分类
能源科技引用本文复制引用
张世锋,李加宝,汪海阁,黄洪春,王成文,崔新颖,黄维安,万磊..泥(页)岩地层漏失诱导裂缝扩展机制及裂缝宽度预测[J].天然气工业,2025,45(4):121-132,12.基金项目
国家自然科学基金基础科学中心项目"超深特深层油气钻采流动调控"(编号:52288101)、国家自然科学基金青年科学基金项目"钻井液劣蚀冷却作用下高温井壁岩石宏细损伤机制研究"(编号:52004037). （编号:52288101）
