测井技术2025，Vol.49Issue(6)：929-941,13.DOI:10.16489/j.issn.1004-1338.2025.06.010
储层工程-地质综合可压裂性评价及水力裂缝扩展优化研究
Integrated Reservoir Engineering-Geological Evaluation of Fracability and Optimization of Hydraulic Fracture Propagation
摘要
Abstract
To optimize the complexity of the fracture network during hydraulic fracturing in reservoirs for enhanced oil and gas recovery,it is essential to integrate geological heterogeneity and engineering parameters,and establish a fracability evaluation model that incorporates geological structure and mechanical properties.An comprehensive fracability index calculation model is developed using an energy-based brittleness index,the in-situ stress difference derived from logging data,and a fracture toughness based on natural fracture parameters and fractal theory.This model comprehensively considers key parameters such as brittleness index,in-situ stress difference,and fracture toughness,overcoming the limitations of traditional brittleness models that overlook the spatial distribution of natural and hydraulic fractures.By utilizing logging data,electrical imaging data,and rock mechanical parameters,a comprehensive fracability evaluation of the reservoir is conducted.Based on the established comprehensive mathematical model for the fracability index,reservoir classification is performed using the particle swarm optimization algorithm,and fracturing process simulation and fracture propagation optimization are carried out with Xsite software.The research results indicate that:① Natural fractures significantly enhance reservoir fracability by reducing the rock effective bulk modulus,inducing stress-driven secondary fracturing,and enhancing the fluid-driven fracture closure effect.After accounting for the influence of natural fractures in well B-01 of the Bohai Bay condensate gas field,the comprehensive fracability index showed a notable improvement.② For oriented perforation designs,particularly horizontal oriented perforations,they promote uniform fracture propagation and reduce near-wellbore fracture tortuosity,thereby increasing the stimulated reservoir volume(SRV).③ Classification based on mechanical parameters such as elastic modulus and Poisson's ratio using the particle swarm optimization algorithmallows the reservoir to be categorized into type I reservoir(high stiffness),type II reservoir(stiffness between type I reservoir and type III reservoir),and type III reservoir(low stress),providing a basis for formulating fracturing strategies.④ Applying hydraulic-fracturing numerical models to different reservoir types reveals pronounced variations in breakdown pressure,specifically:type III reservoir<type II reservoir<type I reservoir.This trend is consistent with the distribution of the minimum horizontal principal stress.⑤ Analysis of normalized breakdown pressure and SRV shows that,among the various parameters affecting fracturing effectiveness,reservoir fracability is the dominant factor controlling both breakdown pressure and SRV;perforation pattern serves as an effective secondary strategy;while the influence of natural fracture length is negligible.In conclusion,the proposed fracability evaluation and fracture propagation prediction method effectively improves the accuracy of fracture morphology control,providing a theoretical basis and technical support for identifying sweet spots and optimizing fracturing techniques in highly heterogeneous reservoirs with developed natural fractures.关键词
水力压裂/天然裂缝/断裂韧性/可压裂性指数/定向射孔/地质力学建模/储层分类/甜点预测Key words
hydraulic fracturing/natural fractures/fracture toughness/fracability index/oriented perforation/geomechanical modeling/reservoir classification/sweet spot prediction分类
天文与地球科学引用本文复制引用
JIE Zhijun,ZHANG Min,SUN Chao,LIU Hongguo,CHEN Xing,ZHANG Zhuo,TANG Jizhou..储层工程-地质综合可压裂性评价及水力裂缝扩展优化研究[J].测井技术,2025,49(6):929-941,13.基金项目
中国海洋石油集团有限公司"十四五"重大项目"测录试关键技术与装备—基于油藏地质的一体化射孔技术装备研制与工程化"(KJGG-2022-1401) （KJGG-2022-1401）
