石油地质与工程2026，Vol.40Issue(1)：24-32,9.DOI:10.26976/j.cnki.sydz.202601004
大牛地气田致密碳酸盐岩储层酸压裂缝扩展规律研究
Study on fracture propagation law of acid fracturing in tight carbonate reservoirs of Daniudi Gas Field
摘要
Abstract
The Lower Paleozoic tight carbonate gas reservoirs in the Daniudi Gas Field of the Ordos Basin are characterized by typical low porosity and ultra-low permeability.Various rock types are developed,including argillaceous dolomite,argillaceous calcareous dolomite,gypsiferous dolomite,and calcareous dolomite.Intraformational and interformational dissolved pores,fractures,and vugs form reservoir space combinations of varying scales with heterogeneous distribution,leading to strong reservoir heterogeneity,big differences in fracture acid-etching characteristics,and considerable challenges in acid fracturing stimulation.To clarify the propagation law of acid-fracturing fractures in tight carbonate reservoirs of the Daniudi Gas Field and improve the pertinence of acid fracturing design,a true triaxial acid fracturing simulation test system was used to investigate the effects of different fracturing fluid systems,injection rates,and natural fracture development characteristics on the initiation and propagation of acid-fracturing fractures.Additionally,3D reconstruction technology was employed to quantitatively characterize the 3D distribution characteristics of fractures after acid fracturing,thereby identifying the dominant controlling factors governing the propagation of acid-fracturing fractures.The results indicate that water fracturing mainly generates single fractures,with significantly lower fracture width,quantity,and complexity compared to acid fracturing,and the fracture width ranges from approximately 0.5 to 1.0 mm.When two types of acid fluids are alternately injected,the acid-fracturing fractures develop obvious wormhole channels with a maximum width of 2.0-3.0 mm,forming a more complex fracture network.An increase in injection rate shortens the fracture initiation time and simultaneously increases the breakdown pressure.A greater number of natural fractures facilitates the connection between acid-fracturing fractures and natural fractures,thereby forming a complex fracture network.This study provides a theoretical basis for the optimal design of acid fracturing in tight carbonate reservoirs of the Daniudi Gas Field and holds important guiding significance for the efficient development of carbonate gas reservoirs关键词
碳酸盐岩储层/酸化压裂/三维重构/裂缝扩展规律Key words
carbonate reservoir/acid fracturing/3D reconstruction/fracture propagation law分类
能源科技引用本文复制引用
张永春,李凌川,毛峥..大牛地气田致密碳酸盐岩储层酸压裂缝扩展规律研究[J].石油地质与工程,2026,40(1):24-32,9.基金项目
中国石油化工股份有限公司科技部项目"致密气藏钻完井及压裂关键技术及应用"(P23156). （P23156）
